Force Sensing Collar

Abstract

A force-sensing collar for use in a can bodymaker for forming metal can bodies using an ironing process, the collar configured to be positioned about a nose portion of a ram of the bodymaker between a circumferentially extending shoulder of the ram and an end face of a punch sleeve, the collar including one or more load cells secured to the collar and configured to generate an electrical signal indicative of a force applied to the collar between the shoulder of the ram and the end face of the punch sleeve during operation of the ram.

Description

[Technical Field]

[0001] The present invention relates to a force-sensing collar for use in a can bodymaker. [Background technology]

[0002] In known bodymakers for producing can bodies by drawing and ironing, a preformed metal cup is fed into the bodymaker and conveyed by a punch at the end of the ram through a series of dies to produce a can body of the desired size and thickness. The series of dies may include a redraw die to reduce the cup's diameter and lengthen its sidewall, and one or more ironing dies to wall-iron the cup into a can body. The area or cradle of the bodymaker frame where the dies are located is known as the "tool pack." The can body conveyed over the punch may eventually come into contact with a bottom-forming tool, or "domer," to form a dome-like shape at the bottom of the can.

[0003] Can bodymakers typically operate at high speeds for extended periods to produce approximately 300 to 400 or more can bodies per minute. However, the quality of the can bodies produced can vary significantly over time due to, for example, changes in machine component configuration, coolant temperature and flow rate, machine lubrication, and / or the quality of the incoming cups (e.g., due to variations in the quality of the metal coil from which the cups are produced). Additionally, one or more components of the bodymaker, particularly the punches, need to be replaced over time as a result of general wear during the operation of the bodymaker. If such components are not replaced in a timely manner, the quality of the can bodies can deteriorate to an unacceptable level, and the component may catastrophically fail, resulting in significant loss of production time, or may be replaced prematurely, leading to scrap. The high-speed, high-volume nature of canmaking means that lost production time can be very costly for manufacturers. Summary of the Invention [Means for solving the problem]

[0004] According to a first aspect of the present invention, there is provided a force-sensing collar for use in a can bodymaker for forming metal can bodies using an ironing process, the collar configured to be positioned about a nose portion of a ram of the bodymaker between a circumferentially extending shoulder of the ram and an end face of a punch sleeve, the collar including one or more load cells secured to the collar and configured to generate electrical signals indicative of force applied to the collar between the shoulder of the ram and the end face of the punch sleeve during operation of the ram.

[0005] One or more load cells may be secured to an inner surface of the collar. The force-sensing collar may include first and second circumferentially extending end shoulders and define a circumferentially extending inner recess on the inner surface of the collar between the first and second circumferentially extending end shoulders, with one or more load cells secured within the recess. The circumferentially extending inner recess may extend completely around the inner surface. The force-sensing collar may further include a plurality of said load cells, the plurality of load cells being substantially equally spaced around the circumferentially extending inner recess. The circumferentially extending end shoulders of the collar may further define a circumferentially extending outer recess on the outer surface of the collar between the circumferentially extending end shoulders.

[0006] The collar can define a channel extending between an inner surface and an outer surface of the collar that, in use, accommodates one or more wires coupled to one or more load cells for transmitting electrical signals generated from the one or more load cells to external equipment. The channel can be defined by a bore extending through the collar or by a clamping plate secured to the inner surface of the collar, the clamping plate configured to prevent movement of the one or more wires relative to the one or more load cells.

[0007] The length of the collar may be from substantially 25 mm to substantially 50 mm. The ratio of the axial length of the one or more load cells to the length of the collar may be substantially 0.72.

[0008] According to a second aspect of the present invention, there is provided an assembly for use in a can bodymaker for forming metal can bodies using an ironing process. The assembly includes a ram having a ram body and a nose portion, the ram body and nose portion defining a circumferentially extending shoulder therebetween, and a punch sleeve having an end face and coaxially disposed around the nose portion such that the end face faces the shoulder. The assembly further includes a collar according to the first aspect, the collar being disposed around the nose portion of the ram between the circumferentially extending shoulder of the ram and the end face of the punch sleeve. The assembly is configured such that a force applied to the punch sleeve in an axial direction toward the shoulder of the ram is transmitted to the collar.

[0009] The assembly may include a punch nose secured to a forward end of the nose portion of the ram and at least partially received within the punch sleeve, the assembly being configured such that a force applied to the punch nose in an axial direction toward the shoulder of the ram is transmitted to the nose portion of the ram rather than to the punch sleeve.

[0010] The ram can include an inner surface defining an interior chamber, the ram further defining a channel extending between the interior chamber and an outer surface of the ram, the channel accommodating the one or more wires such that the one or more wires are received within the interior chamber. Opposite openings of the channels can be aligned with one another.

[0011] The assembly can include a radio transmitter (or other wireless transmitter) disposed within the internal chamber, the transmitter coupled to one or more wires for receiving the generated electrical signals and retransmitting them via a radio or other wireless interface.

[0012] According to a third aspect of the present invention there is provided a bodymaker for forming metal can bodies using the ironing process, the bodymaker comprising an assembly according to the second aspect. [Brief explanation of the drawings]

[0013] [Figure 1] Figure 1a shows an axial cross-sectional view of an exemplary force-sensing collar for use in a can bodymaker, and Figure 1b shows a top view of the exemplary collar of Figure 1a. [Figure 2] 1 shows an axial cross-sectional view of the exemplary collar of FIG. 1a with exemplary dimensions. [Figure 3] 1b shows an axial cross-sectional view of an exemplary assembly with the collar of FIG. 1a. [Figure 4] 3 shows an axial section through a can bodymaker equipped with the assembly of FIG. 2; [Figure 5] 1 shows an exemplary plot of detected force versus time. [Figure 6] 10 illustrates a perspective view of an alternative exemplary force-sensing collar for use in a can bodymaker. DETAILED DESCRIPTION OF THE INVENTION

[0014] 1a and 1b show axial cross-sectional and top views, respectively, of a collar 100 for use in a can bodymaker. In use, the collar 100 is configured to be positioned around the nose portion of the ram of the can bodymaker, between the ram shoulder and the end face of the punch sleeve, as described in more detail below, so that force applied to the punch sleeve toward the ram shoulder is transmitted through the collar. In particular, the collar can be configured to lie around the outer surface of the ram nose portion.

[0015] The collar 100 is generally cylindrical and includes an elongated central cylindrical portion 101 having enlarged end portions 102a, 102b at each end. The collar 100 is annular and defines a central bore configured to receive a nose portion therethrough. The end portions 102a, 102b extend radially inward and outward from the central cylindrical portion 101 to define circumferentially extending inner and outer recesses 103, 104 that extend completely around the collar 100. The end portions 102a, 102b further define respective circumferentially extending shoulders 105a, 105b that face each other across the elongated central cylindrical portion 101. Load cells 108a-108d are secured around an inward-facing surface 110 of the inner recess 103 of the collar 100. 1a-1b includes four load cells 108a-108d (only two of the four are visible in the figures). Of course, those skilled in the art will appreciate that any number of load cells (even a single load cell) may be used. Each of the load cells 108a-108d has a force-sensing axis oriented parallel to the axis 112 of the collar 100.

[0016] In the illustrated example, the load cells 108a-108d are equally spaced, i.e., at 90 degree angular intervals, around the axis 112 of the collar. Those skilled in the art will be able to envision alternative arrangements, such as a collar with separate recesses to accommodate individual load cells, or a collar with a different number of load cells spaced at different intervals.

[0017] In the illustrated example, the circumferentially extending outer recess 104 has substantially the same position and axial extent as the circumferentially extending inner recess 103. Thus, the collar 100 can have a wall having a substantially I-shaped cross-section. Thus, the wall of the collar 100 to which the load cells 108a-108d are secured is thinner than the end portions 102a, 102b. Having a thinner central region of the collar 100 increases the degree of compression of the wall when an axial force is applied, which tends to increase the sensitivity of the load cells secured to that central region.

[0018] The collar 100 defines a channel or bore 122 that provides communication between the interior and exterior of the collar 100. More specifically, the channel 122 extends across one of the ends 102a at an angle relative to the axis 112. The channel 122 accommodates one or more wires coupled to the load cells 108a-d for transmitting electrical signals generated by the load cells 108a-d to external equipment (such as monitoring equipment). As described in more detail below, the outlet opening of the channel 122 aligns with the inlet opening of a channel defined in the bodymaker ram, allowing one or more wires to be fed into an internal chamber within the ram. The collar is rotationally fixed (but importantly not axially fixed) relative to the bodymaker ram to maintain alignment between the outlet opening of the channel 122 and the inlet opening of the channel defined in the ram. For example, a spline or keying structure may be provided between the collar 100 and the ram to prevent rotational movement of the collar 100 relative to the ram. This prevents the wires extending through the channels from being damaged as a result of the rotational movement of the collar 100 .

[0019] Considering the illustrated collar 100, it has the following major dimensions as shown in FIG. A radius A between the axis 112 and the radially innermost surfaces of the ends 102a, 102b of substantially 18.6 mm to 19.2 mm. A radius B of substantially 22.5 mm between the axis 112 and the inwardly facing surface 110 of the inner recess 103. A radius C of substantially 26 mm measured between the axis 112 and the outer recess 104. A radius D of substantially 28 mm between the axis 112 and the radially outermost surfaces of the ends 102a, 102b. Length E substantially 50mm. · An axial length F between the axially inner faces of the ends of substantially 36 mm. Axial length G of substantially 7 mm at both ends. The channel 122 is inclined at an angle θ of substantially 20 degrees relative to the axis 112 .

[0020] Dimensions A, B, C, and D may be selected depending on the size of cans produced by the bodymaker in which collar 100 is used. The dimensions of collar 100 outlined above are for use with a bodymaker configured to produce sleek cans of 33 cl (330 ml) beverages. Those skilled in the art will appreciate that alternatives to the dimensions outlined above may be used for alternative collars configured for use with bodymakers designed to produce cans of different sizes.

[0021] Alternate collars may be provided having substantially the same features as those described above with respect to collar 100, but having different lengths E and different axial lengths F. For example, an alternate collar may have a length E of substantially 25 mm and an axial length F of substantially 11 mm. Further alternate collars may have lengths E within the range of substantially 25 mm to substantially 50 mm. Those skilled in the art will appreciate that in such further alternate collars, the axial length E will vary accordingly. The alternate collars may have the same dimensions A-D and G and θ as described above with respect to collar 100.

[0022] The ratio of the axial length of the load cells 108a-108d to the axial length of the length E of the collar 100 is 0.72 (i.e., as a percentage, 72%). The axial lengths of the load cells 108a-108d may be substantially the same as the axial length F of the collar 100. That is, the axial length of the load cells 108a-108d of the collar 100 may be substantially 36 mm.

[0023] In the alternative collar described above, where the length E is substantially 25 mm and the axial length F is substantially 11 mm, the load cell axial length may be substantially 11 mm. In this alternative configuration, the ratio of the load cell axial length to the collar axial length is also 0.72 (i.e., 72% as a percentage). In a further alternative configuration, the ratio of the load cell axial length to the collar length may be 0.72 (i.e., 72%) or greater, and the minimum collar length E may be substantially 25 mm. In a further alternative configuration, the ratio of the load cell axial length to the collar length may be 0.72 (i.e., 72%) or greater, and the minimum collar length E may be substantially 20 mm. In a further alternative configuration, the ratio of the load cell axial length to the collar axial length may be at least 0.9 (90%), and the minimum collar length E may be substantially 20 mm. In a further alternative configuration, the ratio of the axial length of the load cell to the axial length of the collar may be from 0.35 to 0.95 (ie, 35% to 95%) and the collar length E may be from 25 mm to 50 mm.

[0024] 3 shows an assembly 400 including the collar 100 described above, a ram 402, and a punch 403. The punch 403 includes a punch sleeve 404 and a punch nose 430. The assembly 400 is used in a can bodymaker for forming metal can bodies, as described further below.

[0025] The ram 402 includes a generally cylindrical ram body 408 and a generally cylindrical nose portion 410 of smaller diameter than the ram body 408, with a circumferentially extending shoulder 412 defined at the juncture between the ram body 408 and the nose portion 410. The ram 402 includes an interior surface that defines an internal chamber 416 that extends along the ram body 408 and the nose portion 410. While not described in detail herein, the primary purpose of the internal chamber 416 of the ram 402 is to provide a passageway for directing compressed air toward the end of the punch. The air flow assists in the removal of the formed can body after it is pulled back from the domer and before it enters the tool pack.

[0026] The ram 402 further defines a channel or bore 418 that provides communication between the internal chamber 416 and the exterior of the ram 402. An "inlet" opening of the channel is aligned with an "outlet" opening of the channel 122 of the collar 100 so that one or more wires coupled to the load cells 108a-108d are fed into the internal chamber 416. This configuration avoids the need to route wires through the exterior environment, where oil and debris are likely to be present, during use of the assembly 400.

[0027] The punch sleeve 404 is generally cylindrical and is coaxially disposed around the nose portion 410 of the ram 402. Specifically, the punch sleeve 404 is positioned around the outer surface of the nose portion 410 of the ram 402. The punch sleeve presents an end face 420 that faces right as viewed in FIG. 3 . Also, during use, the collar 100 is disposed around the nose portion 410 of the ram 402, specifically around the outer surface of the nose portion 410 of the ram 402, and is disposed between a shoulder 412 of the ram 402 and the end face 420 of the punch sleeve 404. Importantly, the collar 100 is supported by the nose portion of the ram 402, but is not axially secured or clamped to the ram 402 other than through its abutment with the ram shoulder 412 and the end face 420 of the punch sleeve 404. Similarly, the punch sleeve 404 is not axially secured to the ram nose other than through its abutment with the collar 100 and punch nose 430. As will be explained in more detail below, this configuration allows compression of the collar 100 between the end face 420 of the punch sleeve 404 and the shoulder 412 of the ram 402 during operation of the assembly 400. A total gap of approximately 0.02 mm to approximately 0.051 mm exists between the end faces of the ends 102 a, 102 b of the collar 100 and the punch sleeve 404 and ram shoulder 412. In alternative configurations, no gap may exist. However, in such configurations, the collar is not axially secured or clamped to the ram other than by abutment with the ram shoulder and end faces of the punch sleeve, as discussed above.

[0028] Punch 403 further includes a punch nose 430 fixed to the forward end of nose portion 410 of ram 402 such that axial forces applied to punch nose 430 toward shoulder 412 of ram 402 are transferred directly to nose portion 410 of ram 402. Punch nose 430 is received within punch sleeve 404 such that it undergoes some relative axial movement such that punch nose 430 and punch sleeve 404 together define an end shape suitable for forming a can end in combination with the dome. However, this configuration ensures that axial forces applied to punch nose 430 are not transferred to punch sleeve 104 and therefore not to collar 100.

[0029] The use of collar 100 in assembly 400 will now be described with reference to Figure 4. Figure 4 shows an axial cross section through a portion of a bodymaker including assembly 400.

[0030] As previously described, collar 100 is positioned around nose portion 410 of ram 402 between shoulder 412 of ram 402 and end face 420 of punch sleeve 404. Conventional bodymakers typically install spacer collars between the punch sleeve and shoulder of the ram to resize assembly 400 to accommodate the desired dimensions of the can bodies being formed by the bodymaker. Thus, collar 100 can be retrofitted to existing assembly 400 in place of such spacer collars, thereby serving a dual purpose: as a force measurement tool and a spacer. Of course, collar 100 can be used in combination with one or more spacers located at one or both ends of collar 100.

[0031] When the collar 100 is installed, the load cells 108a-108d are positioned in the space between the collar 100 and the ram nose portion 410. The load cells 108a-108d may be separated from the ram nose portion 410 by a seal. The seal may protect the load cells 108a-108d from harsh external conditions by preventing dirt and / or oil from entering the interior recess 103 in which the load cells 108a-108d are housed. In the exemplary collar 100, the seal comprises a heat shrink film. However, one skilled in the art may envision alternative seal configurations.

[0032] The channel 122 through the collar 100 aligns with a channel 418 through the ram wall. One or more wires of the load cell are routed into the interior chamber 416 of the ram through a channel that is aligned with the interior chamber 416.

[0033] The one or more wires may be electrically connected to an external device comprising one or more computing devices configured to display data derived from the electrical signals generated by the load cells 108a-108d. The connection between the one or more wires and the external device may be wired or wireless. In a wireless configuration, a wireless transmitter is disposed within the internal chamber 416 of the ram 402 and coupled to the one or more wires. The wireless transmitter receives the electrical signals generated by the load cells 108a-108d from the one or more wires and retransmits them via a wireless interface to the external device. The external device may display the data derived from the electrical signals generated by the load cells 108a-108d in real time.

[0034] Prior to ironing, a metal cup to be formed into a can is prepared for ironing. This typically involves cutting / punching a metal disk from a metal sheet and drawing the disk into a cup. The cup may undergo redrawing, as is known in the art. The cup is then placed onto assembly 400, specifically punch 403, and ironed. In the ironing process, the walls of the cup are stretched and thinned to achieve a can shape with a desired wall thickness and length.

[0035] Figure 4 shows a cup 501 positioned on assembly 400. The bottom of cup 501 abuts the front end of punch nose 430, and the walls of cup 501 extend along the outer surface of punch sleeve 404. Figure 4 also shows a bodymaker including tool pack 502 and domer 504. Tool pack 502 includes a series of ironing die assemblies 506, 508, 510.

[0036] The assembly 400 forces the cup 501 axially toward and through the first die assembly 506. As the cup 501 is forced through the first die assembly 506, the walls of the cup are stretched and thinned due to the smaller interior profile of the first die assembly compared to the exterior dimensions of the cup 501. As the cup 501 is forced through the first die assembly 506, a force is applied to the punch sleeve 404 axially toward the shoulder 412 of the ram 402 as a result of friction between the cup 501 and the first die assembly. Because the punch sleeve 404 and collar 100 are not axially clamped to the ram 402, the axial force applied to the punch sleeve 404 is transferred to the collar 100 and acts to compress the collar 100 between the end face 420 of the punch sleeve 402 and the shoulder 412 of the ram 402. Thus, the load cells 108a-108d are compressed and generate an electrical signal indicative of the force being applied to the collar 100.

[0037] The electrical signals are transmitted via one or more wires to an external device to provide an indication of the forces experienced by the ram 402 and / or assembly 400 during the ironing process. In an alternative configuration, the collar and / or assembly may include a transmitter configured to wirelessly transmit the electrical signals generated by the load cells 108a-108d to an external device (e.g., via Bluetooth or other wireless communication protocol).

[0038] The electrical signal containing the force data can be used to determine whether the bodymaker is operating as expected. For example, the data can provide information about punch / ram operation during ironing, allowing the operator to determine when a punch or die needs replacing and indicating whether adjustments are needed to maintain quality and / or prevent tearing. Importantly, this information is provided in real time, allowing the operator to take corrective action before a catastrophic failure occurs, thereby maintaining operational efficiency.

[0039] The process is repeated, with assembly 400 forcing cup 501 through second and third die assemblies 508, 510, until a can body having the desired wall thickness and length is formed. Again, movement of cup 501 and assembly 400 through second and third die assemblies 508, 510 compresses load cells 108a-108d of collar 100, generating an electrical signal indicative of the force applied to collar 100 as assembly 400 passes through the second and third die assemblies. FIG. 5 shows typical outputs from load cells 108a-108d as the assembly performs the drawing and ironing process. Peak 601 may correspond to the point at which assembly 400 is used to perform the drawing process (i.e., the initial step in which a metal disc cut / punched from sheet metal is drawn into a cup, as described above). Peaks 602, 604, and 606 correspond to the points at which assembly 400 passes through first, second, and third die assemblies 506, 508, and 510, respectively.

[0040] As the can body exits the tool pack 502, a doming operation is performed to form a bottom domed profile of the can body. The assembly 400 is forced axially toward the domer 504 so that the bottom of the can body engages the domer 504 and forms a profile at the bottom of the can body that corresponds to the shape of the domer 504.

[0041] Once the can body leaves the tool pack 502, the frictional forces that occurred as the can 501 was pushed through the die assemblies 506, 508, 510 are no longer present and therefore are not transmitted to the punch sleeve 404. This is because the can 501 has completely passed through the die assemblies 506, 508, 510 and the outer dimensions of the assembly 400, particularly the punch sleeve 404, are smaller than the dimensions of the die assemblies 506, 508, 510. As a result, the collar 100 is not subjected to significant forces between the point at which the can body leaves the tool pack 502 and the point at which the doming action begins.

[0042] Assembly 400 is moved axially toward domer 504. During the doming operation, an axial force is transferred from domer 504 to punch sleeve 404 toward shoulder 412 of ram 402 and, consequently, to collar 100. Similar to the process described above, this compresses load cells 108a-d, generating an electrical signal indicative of the force applied to collar 100 during the doming operation. FIG. 5 shows a typical output from the load cells during a doming operation (see output in region 608). Note: The load cells are electrically coupled in parallel with each other so that the force-time profile shown represents an average taken across the load cells. In an alternative configuration, separate profiles corresponding to the output of each single load cell may be provided.

[0043] The punch nose 430 is fixed to the ram 402 but not to the punch sleeve 404, and therefore, a force applied to the punch nose 430 axially toward the shoulder 412 of the ram 402 is transmitted to the nose portion 410 of the ram 402 rather than to the collar 100.

[0044] The above-described collar 100 allows for direct measurement of the forces experienced by the punch and / or ram during ironing and doming operations. This contrasts with configurations known in the art in which a sensing assembly is installed on the tool pack / die and used to provide an indirect method of measuring the forces experienced by the punch / ram. Thus, the described embodiments allow for more accurate monitoring of the forces experienced by the punch / ram during the ironing process. By providing more accurate data to the bodymaker operator, the operator can more accurately identify when a punch or die may need to be replaced. Timely replacement of the punch or die reduces waste and improves operational efficiency by avoiding costly and time-consuming machine / process breakdowns resulting from punch and / or die wear. Even more advantageously, the collar can be retrofitted to existing configurations.

[0045] FIG. 6 is a perspective view of an alternative collar. The overall structure of collar 600 is similar to that of the previously described collars, except that a clamp 601 is provided for attachment to the inner surface of one end 603 of the collar, e.g., by a pair of bolts. The clamp sits within a correspondingly shaped recess in the inner surface so that the collar lies substantially flush with the inner surface and does not interfere with axial movement of the collar relative to the ram on which the collar is positioned. Together, clamp 601 and the inner surface of the collar define a channel 602 through which one or more wires coupled to a load cell can pass. It will be appreciated that the channel, extending from the interior to the exterior of the ram, is positioned so that the wires can pass directly from channel 602 into the ram. Clamp 601 can be tightened against the collar to secure the wires in place. This prevents "external forces" from pulling the wires against the load cell and thereby damaging the connection.

[0046] It will be appreciated by those skilled in the art that various modifications can be made to the above-described embodiments without departing from the scope of the present invention.

Claims

1. 1. A force-sensing collar for use in a can bodymaker for forming metal can bodies using an ironing process, the collar configured to be positioned about a nose portion of a ram of the bodymaker between a circumferentially extending shoulder of the ram and an end face of a punch sleeve, the collar including one or more load cells secured to the collar and configured to generate an electrical signal indicative of a force applied to the collar between the shoulder of the ram and the end face of the punch sleeve during operation of the ram.

2. The force-sensing collar of claim 1 , wherein the one or more load cells are secured to an inner surface of the collar.

3. 3. A force-sensing collar as described in claim 1 or 2, comprising first and second circumferentially extending end shoulders and defining a circumferentially extending inner recess on an inner surface of the collar between the first and second circumferentially extending end shoulders, the one or more load cells being secured within the recess.

4. The force-sensing collar of claim 3 , wherein the circumferentially extending inner recess extends completely around the inner surface.

5. 5. A force-sensing collar according to claim 3 or 4, comprising a plurality of said load cells, said plurality of load cells being substantially equally spaced around said circumferentially extending inner recess.

6. 6. A force-sensing collar according to claim 3, wherein the circumferentially extending end shoulders of the collar further define a circumferentially extending outer recess in an outer surface of the collar between the circumferentially extending end shoulders.

7. 7. A force-sensing collar according to claim 1, wherein the collar defines a channel extending between an inner surface and an outer surface of the collar and accommodating, in use, one or more wires coupled to the one or more load cells for transmitting the generated electrical signals from the one or more load cells to an external device.

8. 8. The force-sensing collar of claim 7, wherein the channel is defined by a bore through the collar or by a clamping plate secured to an interior surface of the collar, the clamping plate configured to prevent movement of the one or more wires relative to the one or more load cells.

9. A force-sensing collar according to any preceding claim, wherein the length of the collar is from substantially 25 mm to substantially 50 mm.

10. 10. A force-sensing collar according to any one of claims 1 to 9, wherein the ratio of the axial length of the one or more load cells to the length of the collar is substantially 0.

72.

11. A force-sensing collar according to any one of claims 1 to 10, wherein the collar is configured to lie around an outer surface of a nose portion of the ram.

12. 1. An assembly for use in a can bodymaker for forming metal can bodies using an ironing process, said assembly comprising: a ram comprising a ram body and a nose portion defining a circumferentially extending shoulder between the ram body and the nose portion; a punch sleeve having an end surface, the punch sleeve being coaxially disposed around the nose portion such that the end surface faces the shoulder; 12. A collar according to any one of claims 1 to 11, disposed about a nose portion of the ram between a circumferentially extending shoulder of the ram and an end face of the punch sleeve. Equipped with The assembly is configured such that a force applied to the punch sleeve in an axial direction toward the shoulder of the ram is transmitted to the collar.

13. 13. The assembly of claim 12, wherein the collar is not axially secured to the nose portion of the ram other than by abutment with a circumferentially extending shoulder of the ram and an end face of the punch sleeve.

14. 14. An assembly according to claim 12 or 13, comprising a punch nose fixed to a forward end of a nose portion of the ram and at least partially received within the punch sleeve, the assembly being configured such that a force applied to the punch nose in an axial direction towards the shoulder of the ram is transmitted to the nose portion of the ram rather than to the punch sleeve.

15. 15. The assembly of claim 14, wherein the punch sleeve is not axially secured to the nose portion of the ram other than by abutment with a circumferentially extending shoulder of the ram and the punch nose.

16. 16. An assembly according to any of claims 12 to 15, comprising the collar of claim 7, wherein the ram has an inner surface defining an internal chamber, the ram further defining a channel extending between the internal chamber and an outer surface of the ram, the channel accommodating the one or more wires such that the one or more wires are received within the internal chamber.

17. The assembly of claim 16 , wherein opposing openings of the channels are aligned with one another.

18. 18. The assembly of claim 16 or 17, comprising a wireless transmitter disposed within the internal chamber, the wireless transmitter coupled to the one or more wires for receiving the generated electrical signals and retransmitting the electrical signals via a wireless interface.

19. 19. A bodymaker for forming metal can bodies using the ironing process, comprising an assembly according to any one of claims 12 to 18.

Images