Automated method of dispensing

Abstract

There is an automated method (100 figure 1, 200 figure 6) of dispensing a compressible thixotropic thermal barrier material on to a vehicle part, the method comprising: conveying a first material to a

Description

TECHNICAL FIELD The present disclosure relates to an automated method of dispensing a compressible thixotropic thermal barrier material on a vehicle part. Aspects of the invention relate to a method. BACKGROUND Electric vehicle (EV) batteries must be constructed so that heat transfer to neighbouring cells in a battery pack is reduced. One way to do this is to provide a thermal barrier material such as 3M™ Thermal Barrier 5000 Series (a.k.a. ATP) in the battery module. Such thermal barrier materials insulate the cells of the battery, absorbing and dissipating heat. Arrangement of such thermal barrier materials in a battery is very difficult due to their compressible and thixotropic nature. Up to now, mastic-style cartridges have been used to deposit such materials manually in a vehicle battery. However, given the quantity of thermal barrier material needed to insulate each electric battery, the costs associated with this application have become very high. It is an aim of the present invention to address one or more of the disadvantages associated with the prior art. SUMMARY OF THE INVENTION Aspects and embodiments of the invention provide a method as claimed in the appended claims. According to an aspect of the present invention, there is provided an automated method of dispensing a compressible thixotropic thermal barrier material on a vehicle part, the method comprising: conveying a first material to a mixing chamber; conveying a second material to the mixing chamber; combining the first material and the second material to form the compressible thixotropic thermal barrier material in the mixing chamber, and activating a dispenser to dispense the thermal barrier material on the vehicle part. By way of this automated process, it has been possible to improve dispense efficiencies of the compressible and thixotropic thermal barrier material. For example, operating two dispense stations each carrying out the automated method unlocks an approximate 100% increase in production rate compared to the manual application methods of the prior art, and allows one vehicle part (e.g., in the form of a vehicle battery subassembly) to be processed every 16 seconds Substantial additional savings are possible by buying the compressible thixotropic thermal barrier material in bulk (e.g., in containers in the form of barrels) rather than in mastic-style cartridges. While the dispenser dispenses the thermal barrier material on the vehicle part, the dispenser may be moved such that a continuous line of thermal barrier material is dispensed on the vehicle part. This dispenses a continuous bead on the vehicle part. In an embodiment, the method further comprises a step of activating at least one positive displacement pump to convey the thermal barrier material from the mixing chamber to the dispenser. The step of conveying a first material to a mixing chamber may comprise conveying a first material contained in a first container to the mixing chamber. The step of conveying a second material to a mixing chamber may comprise conveying a second material contained in a second container to the mixing chamber. In an embodiment, the dispenser comprises a dispenser valve arrangeble in a closed position, in which the dispenser valve prevents thermal barrier material being dispensed by the dispenser, and in an open position, in which thermal barrier material can be dispensed by the dispenser. Activating the dispenser to dispense the thermal barrier material may comprise arranging the dispenser valve in the open position. The dispenser valve advantageously prevents the compressible thixotropic material from spreading out from the dispenser when dispense is not needed. Optionally, the dispenser valve is a ball valve. In an embodiment, activating the dispenser to dispense the thermal barrier material comprises: waiting a first predetermined period after arranging the dispenser valve in the open position, and activating the at least one positive displacement pump. Waiting 0.1s or so after opening the nozzle valve before activating the dispenser pumps ensures the correct pre-pressure of the thermal barrier material for dispense, and hence consistent dispensing thereof. If the pre-pressure of the thermal barrier material is too high, then too much thermal barrier material will be dispensed first, while if the pre-pressure of the thermal barrier material is too low, then not enough thermal barrier material will be dispensed initially. In an embodiment, the method further comprises a step of deactivating the dispenser to cease dispense of the thermal barrier material. The step of deactivating the dispenser may comprise: arranging the dispenser valve in the closed position, waiting a second predetermined time, and deactivating the at least one positive displacement pump. Waiting 0.1s or so after closing the nozzle valve before deactivating the dispenser pumps ensures the right pre-pressure the thermal barrier material for the next dispense. Optionally, the first predetermined period and / or the second predetermined period is between 0.05 and 0.15 seconds. The first predetermined period and the second predetermined period may be the same. Optionally the first predetermined period and / or the second predetermined period is 0.1 seconds. In an embodiment, the dispenser is only activated to dispense the thermal barrier material when a dispensing request is received. In an embodiment, the method further comprises a step of purging the thermal barrier material contained in the dispenser. The step of purging may be performed when: (i) a dispensing request has been received, and (ii) either there has been more than a third predetermined period since the dispenser last dispensed thermal barrier material on a vehicle part, or there has been more than the third predetermined period since the dispenser was last purged. Purging the dispenser means activating it to dispense some thermal barrier material (e.g., 350ml thereof), but not onto a vehicle part. Instead, the material is expelled or disposed only to clean or clear the dispenser of hardening thermal barrier material. Purging the dispenser when a dispensing request has been received and when there has been more than the third predetermined period of time since the last dispense or purge is advantageous. Around 5 minutes after the first and second material have been combined to form the thermal barrier material, the material starts to harden and so it is advantageous to purge the dispenser before performing a dispense into a vehicle part, to ensure that it is only provided with thermal barrier material in fluid form. By performing the purge only when the dispensing request has been received, unnecessary waste of thermal barrier material in the dispenser is avoided. Additionally or alternatively, the step of purging may be performed when either there has been more than a fourth predetermined period since the dispenser last dispensed thermal barrier material on a vehicle part or there has been more than the fourth predetermined period since the dispenser was last purged. Such a purging step is therefore performed irrespective of whether a dispensing request has been received. Purging the dispenser regardless of whether a dispensing request has been received, but when there has been more than 60 minutes since the last dispenser or purge is advantageous. Around sixty minutes after the first and second material have been combined to form the thermal barrier matter, the material hardens to such an extent that the system (e.g., the mixing chamber and / or the dispenser) can become completely blocked and parts need to be replaced. Hence, the dispenser is advantageously auto-purged after around sixty minutes of non-operation to avoid this from happening. Optionally, the third predetermined period is between 4 and 6 minutes, and / or the fourth predetermined period is between 55 and 65 minutes. Optionally, the third predetermined period is 5 minutes. In some examples the fourth period is longer than the third period. Optionally, the fourth predetermined period is 60 minutes. The method may further comprise an (e.g., initial) step of providing the vehicle part. This step may be fully automated e.g., using a handling robot, conveyor and / or platen. In an embodiment, the vehicle part is a vehicle battery subassembly. In an embodiment, the thermal barrier material is a silicon paste comprising polymer microbubbles. Optionally, the thermal barrier material is the 3M Thermal Barrier 5000 Series. The invention extends to a computer readable instructions which, when executed by one or more processors, cause the one or more processors to perform the method described above. Within the scope of this application, it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and / or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and / or features of any embodiment can be combined in anyway and / or combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and / or incorporate any feature of any other claim although not originally claimed in that manner. BRIEF DESCRIPTION OF THE DRAWINGS One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows a flow diagram depicting the steps of an automated method of dispensing a compressible and thixotropic thermal barrier material on a vehicle part in accordance with an embodiment of the invention; Figure 2 shows a perspective view of a thermal barrier material system that is configured to perform the automated method of Figure 1; Figure 3 shows a cross-sectional side view of a barrel for use in the thermal barrier material system of Figure 2; Figure 4 shows a perspective view of a mixing and dispensing system for the thermal barrier material system of Figure 2; Figure 5 shows a schematic view of a control system for controlling the mixing and dispensing system of Figure 4; and Figure 6 shows a flow diagram depicting the steps of an automated method of dispensing a compressible and thixotropic thermal barrier material on a vehicle part in accordance with another embodiment of the invention. DETAILED DESCRIPTION An automated method 100 of dispensing a compressible and thixotropic thermal barrier material on a vehicle part (not shown) in accordance with an embodiment of the present invention is described herein with reference to the accompanying Figure 1. With reference to Figure 1, the method 100 comprises the following steps: conveying a first material 118a to a mixing chamber 112 (step 102), conveying a second material 118b to the mixing chamber 112 (step 104), combining the first material 118a and the second material 118b to form the compressible thixotropic thermal barrier material in the mixing chamber 112 (step 106) and activating a dispenser 114 to dispense the thermal barrier material on the vehicle part (step 108). Byway of this automated process, it has been possible to improve dispense efficiencies of the compressible and thixotropic thermal barrier material. For example, operating two dispense stations 116 each carrying out the automated method 100 unlocks an approximate 100% increase in production rate compared to the manual application methods of the prior art, and allows one vehicle part (e.g., in the form of a vehicle battery subassembly) to be processed every 16 seconds. Furthermore, this results in a saving associated with freeing up 22 manual workers. Substantial additional savings are possible by buying the compressible thixotropic thermal barrier material in bulk (e.g., in containers 110 in the form of barrels) rather than in mastic-style cartridges. Now more detail about the automated method 100 will be provided, starting with a discussion of the thermal barrier material. Thermal barrier material The thermal barrier material is configured to provide a thermal and electrical barrier to the vehicle part. When applied to a vehicle part in the form of a vehicle battery subassembly, it beneficially reduces heat transmission between cells. It does this by insulating the cells, absorbing and dissipating heat, and thereby stopping the spread of thermal energy to adjacent cells. In some embodiments, the thermal barrier material takes the form of a silicon paste comprising polymer microbubbles such as the 3M™ Thermal Barrier 5000 Series. The thermal barrier material may have different properties to the first and second materials 118a, 118b that it is formed from. Typically, the first and second materials 118a, 118b only begin to cure when the two materials are mixed together. In this way, the first and second materials 118a, 118b may be easier to handle in isolation, and more difficult to handle after being mixed together. The mixed thermal barrier material is both compressible and thixotropic, which make it even more difficult to handle and deposit. Thixotropy is related to the change in viscosity under shear stress, while compressibility pertains to the change in volume under pressure. A ‘bead’ of the thermal barrier material relates to a continuous line or ‘drop’ of the thermal barrier material e.g., deposited on a vehicle part. Thermal barrier material system A thermal barrier material system 120, which is configured to perform the steps of the automated method 100 above, will now be described with reference to Figure 2. The thermal barrier material system 120 is arranged within a dispense station 116 in which dispense occurs, and comprises a supply system 122 for conveying the first and second materials 118a, 118b from respective first and second containers 110a, 110b to the mixing chamber 112 (i.e., steps 102 and 104 of the automated method 100) and a mixing and dispensing system 124 for combining the first material 118a and the second material 118b to form the thermal barrier material and dispensing the thermal barrier material on the vehicle part (i.e., steps 106 and 108 of the automated method 100). It is noted that the first and second steps 102, 104 can be performed in any order or at the same time, as necessary. The supply system As stated above, the supply system 122 is configured to convey the first and second materials 118a, 118b from the respective firstand second containers 110a, 110b to the mixing and dispensing system 124. The supply system 122 of Figure 2 comprises four barrel-emptying units or cabinets 130. Each barrelemptying unit 130 receives a container or barrel 110 containing either the first material 118a or the second material 118b, and draws the respective first or second material 118a, 118b therefrom. To this end, the barrel emptying units may be ViscoTec MT-XL. In one embodiment, the supply system 122 comprises two barrel-emptying units 130 for each of the first and second materials 118a, 118b - i.e., two first material barrel-emptying units 130a and two second material barrel-emptying units 130b. This beneficially allows one barrel 110 for each material to be used for supply, and another to be lined up and ready to be used when the barrel 110 is empty, thereby precluding any breaks in supply of the first and second material 118a, 118b and allowing the entire thermal barrier material system 120 to be used continually. In other words, there are “now and next” barrels 110 for each of the first and second materials 118a, 118b in the supply system 122. In other embodiments, the supply system 122 comprises only two barrel-emptying units 130: one 130a for the first material container 110a and the other 130b for the second material container 110b. Here, there may be short delays in the running of the thermal barrier material application system after one barrel 110 is emptied and replaced. Barrel In Figure 3, one particularly advantageous example of a container or barrel 110 is shown, with the material (which is either the first or second material 118a, 118b) arranged at the bottom thereof. In this example, the barrel 110 has a cylindrical shape, straight sides, and an open top, although other configurations are possible. At the top of the barrel 110, the barrel 110 is provided with a follower-plate 132 arranged to apply downward pressure on the material contained in the barrel 110, thereby facilitating efficient extraction of the material from the barrel 110. The follower-plate 132 includes a central opening in the centre thereof through which the material is guided as it is conveyed out of the barrel 110. Because of the central opening, the follower-plate 132 can be understood as toroidal. The barrel 110 is further provided with a main conduit 134 such as a hose which conveys material that has passed through the central opening of the follower-plate 132 to the mixing and dispensing system 124, To this end, the hose is lined up with the central opening of the follower-plate 132 and extends upwards therefrom. Within the hose, the barrel 110 includes a barrel pump (not shown), which is arranged to pump the material from the base of the barrel 110, through the opening of the follower-plate 132, and out of the barrel 110 through the hose. In one embodiment, the barrel pump is a positive-displacement pump because the first and second materials 118a, 118b are sensitive to shear and can become highly fluid if disturbed too much by other types of pumps. The barrel 110 may be further provided with a Venturi system (not shown) configured to create a negative pressure within the barrel 110 and draw out air trapped in the material as the follower plate pushes down on it. To this end, the follower plate defines at least one off-centre opening away from the central opening of the follower plate. A subsidiary conduit 136 such as a pipe is arrange to extend upward from the or each off-centre opening and connect to the Venturi system. The or each subsidiary conduit 136 may have a smaller diameter than the main conduit 134. The barrel 110 is further provided with at least one foam pad 138 to (i) ensure a uniform vacuum in the barrel 110 and (ii) protect the Venturi system from sucking up the material. To this end, the at least one foam pad 138 is arranged below the follower plate and hence below the subsidiary conduit(s) 136. The example of Figure 3 has two foam pads 138 with one arranged directly on top of the other, but in other examples there can be other numbers of foam pads 138 and / or the foam pad(s) 138 can be arranged in different ways. The at least one foam pad 138 also defines a central opening arranged at their centre, through which material passes as it exits the barrel 110. In this way, the at least one foam pad 138 can also be understood as toroidal. The barrel 110 may be advantageously provided with a separator or insert 140 which is arranged below the at least one foam pad 138 and above the material in the barrel 110. The separator 140 has a central opening arranged at its centre, and is shaped so that it directs material towards the centre of the barrel 110 as it is drawn upwards through the barrel 110. Because of its central opening, the separator 140 can also be understood as toroidal. The underside of the separator 140 may be advantageously sloped (or chamfered) upwards and inwards towards the central opening. Such a conical shape further acts to direct the material to the centre of the barrel 110. In this way, the separator 140 advantageously prevents the material from coming into contact with the at least one foam pad 138, which would otherwise draw oil out from the material, causing it to cake and spoil. Mixing and dispensing system As stated above, the mixing and dispensing system 124 is configured to combine the first material 118a and the second material 118b to form the thermal barrier material and then dispense the thermal barrier material on the vehicle part. To this end, the mixing and dispensing system 124 is provided with the dispenser 114 such as the one shown in Figure 2, and better seen in Figure 4. The dispenser 114 may be a ViscoTec ViscoDuo. Dispenser The dispenser 114 of Figures 2 and 4 includes firstand second pump chambers 150a, 150b, a two-channel manifold 152, the mixing chamber (or static mixer) 112 and a nozzle 154, each of which will now be described in turn. The first and second pump chambers 150a, 150b are elongate chambers that extend downwards from the top of the dispenser 114. The pump chambers 150a, 150b are arranged side-by-side, but separate from one another. The first material 118a enters the dispenser 114 through the top of the first pump chamber 150a, while the second material 118b enters the dispenser 114 through the top of the second pump chamber 150b. To this end, a first main conduit 134a couples a first barrel 110a containing first material 118a to the first pump chamber 150a, while a second main conduit 134b couples a second barrel 110b containing second material 118b to the second pump chamber 150b. The barrel pumps of the first and second barrels 110a, 110b convey the first and second materials 118a, 118b to the first and second pump chambers 150a, 150b via the first and second main conduits 134a, 134b. Once inside the pump chambers 150a, 150b, the first and second materials 118a, 118b are then conveyed downwards. To this end, the first pump chamber 150a may contain a first dispenser pump (not shown) and the second pump chamber 150b may contain a second dispenser pump (not shown). The dispenser pumps are configured to convey the first and second materials 118a, 118b through the pump chambers 150a, 150b and down through the rest of the dispenser 114. To facilitate this, the dispenser pumps may take the form of positive displacement pumps and may each include a corkscrew feed. In particular, they may each have a single helix rotor arranged to rotate within a double helix stator. This pushes the materials through the dispenser 114 with positive displacement (force) instead of pressure. The first and second pump chambers 150a, 150b each may include a pump inlet pressure sensor (not shown) to measure the inlet pressure to the pumps therein. The purpose of these pump inlet pressure sensors will be explained below. Below the first and second pump chambers 150a, 150b is the two-channel manifold 152 of the dispenser 114. The manifold 152 is arranged to receive the first and second materials 118a, 118b from the first and second pump chambers 150a, 150b and separately convey the first and second materials 118a, 118b into the static mixer 112, where only then will they be combined together. To this end, the two-channel manifold 152 defines a first channel (not shown) in fluid connection with the first pump chamber 150a and a second channel (not shown) in fluid connection with the second pump chamber 150b. The first and second channels extend side-by-side, but separately, through the manifold 152. Hence, in the manifold 152, the first and second materials 118a, 118b are still kept fluidly apart (i.e., as they were in the firstand second pump chambers 150a, 150b). The first and second channels each may include a manifold pressure sensor (not shown) to measure the pressure therein. The purpose of these manifold pressure sensors will be explained below. Below the two-channel manifold 152 is the static mixer 112 of the dispenser 114. The static mixer 112 is configured to receive the first and second materials 118a, 118b from the first and second channels of the manifold 152, and mix, and hence combine, the first and second material 118a, 118b together to form the thermal barrier material. The thermal barrier material then exits the static mixer 112 through the exit at the bottom thereof. To this end, the static mixer 112 takes the form of an elongate tube extending downwards. The static mixer 112 may be removable and disposable, such that if the thermal barrier material within the static mixer 112 is left too long and it hardens to such an extent that it clogs up the static mixer 112, it can easily be removed and replaced by another. Below the static mixer 112, the nozzle 154 of the dispenser 114 is arranged. The nozzle 154 is configured to receive the thermal barrier material from the static mixer 112 and dispense the thermal barrier material onto a vehicle part when activated to do so. To this end, the nozzle 154 contains a nozzle or dispenser valve 156 that opens and closes the nozzle 154 depending on its position within the nozzle 154. When the valve 156 is in the closed position, the valve 156 prevents thermal barrier material being dispensed through the nozzle 154 and the thermal barrier material from the static mixer 112 is maintained in the nozzle 154. On the other hand, when the valve 156 is in the open position, the thermal barrier material can be dispensed out of the nozzle 154, in particular under the action of the dispenser pumps (i.e., when activated). Hence, to activate the dispenser 114 to dispense the thermal barrier material, the dispenser valve 156 is first arranged in the open position. The use of the nozzle or dispenser valve 156 is particularly advantageous because of the characteristics of the combined thermal barrier material. In particular, due to its compressibility, the combined thermal material would continually expand out the end of the nozzle 154 if a valve 156 were not used. By using the valve 156, the thermal barrier material is maintained with inside the nozzle 154 of the dispenser 114 when dispense is not needed, and hence it allows fine control of the dispense of the thermal barrier material. In one embodiment, the valve 156 is a ball valve, which can advantageously be used to ensure quick, closing and opening of the nozzle 154. Other types of valve such as a needle valve may also be used. To summarise the flow of fluids through the dispenser 114 therefore: there are two separate and distinct paths for each of the first and second materials 118a, 118b from the barrels 110a, 110b to the manifold 152. Only at the static mixer 112 are the first and second barrier materials brought into contact with each other and combined to form the thermal barrier material. Then, the combined thermal barrier material is conveyed to the nozzle 154 for dispensing. In this way the product can only begin to cure in the static mixer 112 and not before. Robot To control the operation of the dispenser 114, the mixing and dispensing system 124 is further provided with a robot 160. The robot 160 is configured to move the dispenser 114 so as to position its nozzle 154 in the right place for dispensing. In the example of Figure 2, the robot 160 is an articulated robot, and the dispenser 114 is mounted on an arm 162 of the articulated robot, although other arrangements are possible. The robot 160 may be an ABB IRB 6700. After the robot 160 arranges the nozzle 154 in the right position, the robot 160 is then configured to activate the dispenser 114 to perform a dispensing operation. To this end, the robot 160 activates the dispenser pumps and opens the nozzle valve 156. As will be detailed below, by adjusting the two together, the robot 160 can finely control the dispense of the thermal barrier material out of the nozzle 154. While the dispenser 114 dispenses the thermal barrier material on a vehicle part, the robot 160 may move the dispenser 114 such that a continuous line of thermal barrier material is dispensed on the vehicle part. This allows continuous beads or lines of thermal barrier material to be dispensed on the vehicle part. Control system To carry out the above operations of the robot 160, the robot 160 is provided with a control system 170 illustrated in Figure 5. The control system 170 of the robot 160 is configured to activate the dispenser 114 to dispense thermal barrier material on (or in) the vehicle part in dependence on detection of said vehicle part. To this end, the control system 170 comprises one or more controllers 172, although it will be appreciated that this is merely illustrative. The controller 172 comprise processing means 174 and memory means 176. The processing means 174 may be one or more electronic processing devices which operably execute computer-readable instructions. The memory means 176 may be one or more memory devices. The memory means 176 is electrically coupled to the processing means 174. The memory means 176 is configured to store instructions, and the processing means 174 is configured to access the memory means 176 and execute the instructions stored thereon. The controller 172 further comprises an input means 178 and an output means 180. The input means 178 may comprise an electrical input of the controller 172. The output means 180 may comprise an electrical output of the controller 172. The input means 178 is arranged to receive an input signal or dispensing request from an input sensor (e.g., in the form of a camera) (not shown), the input signal corresponding to the identification of the presence of the vehicle part for processing (e.g., by way of an image taken by the camera). Additionally, the input signal may further include the identification of the type of the vehicle part by the input sensor (also e.g., through the image taken by the camera). The input sensor may be arranged on the robot 160, the dispenser 114 or at any other suitable location in the dispense station 116. The output means 180 is arranged to output an output signal or dispensing command to activate the dispenser 114 to dispense the thermal barrier material in dependence on the input signal or dispensing request. In dependence on an identification of the type of the vehicle part, the robot 160 may adapt the composition of the thermal barrier material to be dispensed (e.g., by independently controlling the operation of the first and second dispenser pumps to achieve the desired composition or recipe of thermal barrier material for the vehicle part) and / or control how the dispenser 114 is moved (its dispense path) and / or when the dispenser 114 dispenses (its activation sequence) to achieve a desired arrangement of dispensed thermal barrier material on or in the vehicle part. The control system 170 may be arranged within the robot 160, or outside of the robot 160 and elsewhere in the thermal barrier material system 120. Dispensing process Figure 6 illustrates a method 200 of dispensing thermal barrier material on a vehicle part according to an embodiment of the invention. The method 200 may be performed by the thermal barrier material system 120 illustrated in Figure 2 and described above, and all steps thereof are fully automated (i.e., it can be performed without human intervention) unless explicitly stated otherwise below. In step 202, a vehicle part - e.g., in the form of a battery subassembly - is transferred by a transfer system (not shown) into the dispense station 116 where the thermal barrier material system 120 is located. The transfer system then arranges the vehicle part on top of a movable platen (not shown). To this end, the transfer system may comprise a conveyor (not shown) moving the vehicle part into the station and a handling robot (not shown) for moving the vehicle part from the conveyer onto the platen. In step 204, the movable platen, supporting the part, is moved upwards. Rails (not shown) extending parallel to the floor are provided thereabove, so as to stop the platen moving beyond a certain height, hence arranging the vehicle part at the right height for use with the dispenser 114. In this way, an advantageous vertical distance between the nozzle 154 of the dispenser 114 and the vehicle part is achieved, thereby allowing improved dispense on the vehicle part by the dispenser 114. Then in step 206, the input sensor of the robot 160 is used to detect whether the vehicle part is present. Additionally, the vehicle part may be checked at this stage and / or its type identified by the input sensor of the robot 160. On the basis of the detected type of vehicle part, the control system 170 of the robot 160 may select the relevant composition of thermal barrier material to be dispensed and / or the relevant dispense path and activation sequence for the dispenser 114 (to achieve the desired arrangement of dispensed thermal barrier material on or in the vehicle part). In one embodiment, there are four different robot dispense paths that can be selected depending on the vehicle part to be processed. Then in step 208, the control system 170 uses the pump inlet pressure sensors in the pump chambers 150a, 150b to assess whether the inlet pressure to the first and second pumps is greater than an inlet pressure threshold. If the measured inlet pressures exceed the inlet pressure threshold, the process moves onto step 214. However, if at least one of the measured inlet pressures is less than the inlet pressure threshold, the process moves onto step 210, wherein an indication is provided to e.g. operators that the minimum inlet pressure to the pumps has not been achieved and that there is a fault in the system. This could indicate that there is not enough of the first and / or second material 118a, 118b being provided by the supply system 122, or that the material(s) are insufficiently compressed in the system such that they cannot move and are causing a blockage (they will only move when sufficiently compressed). Thereafter, in step 212, the cause of the fault is investigated and, where appropriate, the issue with the supply system 122 is resolved (e.g., with input from an operator if needed). Only then, does the process return to step 208 to reassess whether the measured inlet pressures now exceed the inlet pressure threshold, to allow the process to move onto step 214. Steps 214 and 216 relate to purging of the dispenser 114. Purging of the dispenser 114 relates to the robot 160 activating the dispenser 114 to dispense all of the thermal barrier material contained in the static mixer 112 and nozzle 154. This may be around e.g., 350ml of thermal barrier material. During purging, the thermal barrier material is not dispensed onto a vehicle part. Instead, the material is expelled elsewhere or disposed. This therefore cleans or clears the dispenser 114 of all thermal barrier material contained in the static mixer 112 and nozzle 154. In step 214, the control system 170 of the robot 160 assesses whetherthere has been more than 5 minutes or so (e.g., between 4 and 6 minutes) since either the dispenser 114 was last used to dispense thermal barrier material onto a vehicle part or the dispenser 114 was last purged. If it has been more than 5 minutes or so, the process moves onto step 216 where the thermal barrier material contained in the static mixer 112 and nozzle 154 is purged by the dispenser 114, and the process then moves onto step 218. If it has been less than 5 minutes or so, the process moves directly from step 214 to step 218 (i.e., bypassing step 216). The reason purging the dispenser 114 when a dispensing request has been received and when there has been more than five minutes or so since the last dispense or purge is as follows. Around 5 minutes after the first and second materials 118a, 118b have been combined to form the thermal barrier material in the static mixer 112, the material starts to harden and so it is advantageous to purge the static mixer 112 and the nozzle 154 before performing a dispense into a vehicle part, to ensure that the vehicle part is only provided with thermal barrier material in fluid form. By performing the purge only when a dispense operation is needed, unnecessary waste of thermal barrier material is avoided. In one embodiment, regardless of whether a dispense operation is needed (i.e., whether an input signal or dispensing request is received), if there has been more than 60 minutes or so (e.g., between 55 and 65 minutes) since either the dispenser 114 was last used to dispense thermal barrier material onto a vehicle part or the dispenser 114 was last purged, the thermal barrier material contained in the static mixer 112 and the nozzle 154 will be purged by the dispenser 114. Such a purge is undertaken irrespective of whether a dispensing request has been received because around sixty minutes after the first and second materials 118a, 118b have been combined to form the thermal barrier matter, the material hardens to such an extent that the system (e.g., the mixing chamber 112 and / or the dispenser 114) can become completely blocked and parts need to be replaced. Hence, the dispenser 114 is advantageously auto-purged after around sixty minutes of non-operation to avoid this from happening. In step 218 (following either step 214 or step 216), the robot 160 begins its nozzle check routine. In step 220, the nozzle check routine begins by checking the nozzle 154 is arranged at the right height above the vehicle part and / or checking it is sufficiently clean for dispensing. If the nozzle 154 is at the wrong height and / or it is insufficiently clean, the dispenser 114 would not be able to dispense the thermal barrier material accurately enough, and so the process moves onto step 222, where an indication is provided to e.g. operators that the nozzle check has failed. Then the process then moves onto step 224, where the nozzle 154 is cleaned and / or re-aligned as necessary (e.g., with input from an operator if needed). Only then, does the process return to step 208 to start the process again at this step of the method 200. If the nozzle 154 is at the correct height and / or is sufficiently clean, the process moves onto step 226, where the robot 160 removes excess thermal barrier material from the end of the nozzle 154 using e.g., piano wire. This advantageously ensure the nozzle 154 is drip free prior to the dispense operation. Then in step 228, the dispensing operation begins with the robot 160 moving the dispenser 114 to the bead start position. Then in step 230, the robot 160 starts to move the dispenser 114 at a set speed if a continuous line of thermal barrier material is to be dispensed. In step 232 (which may occur at the same time as step 230), the nozzle valve 156 is opened. Then in step 234, there is a delay lasting 0.1s or so (e.g. between 0.05 and 0.15 seconds), before step 236 then starts, in which the dispenser pumps are activated. The dispenser pumps act to drive thermal barrier material out of the nozzle 154 and onto the vehicle part arranged on the platen. Waiting 0.1s or so after opening the nozzle valve 156 before activating the dispenser pumps ensures the correct pre-pressure of the thermal barrier material for dispense, and hence consistent dispensing thereof. If the pre-pressure of the thermal barrier material is too high, then too much thermal barrier material will be dispensed first, while if the pre-pressure of the thermal barrier material is too low, then not enough thermal barrier material will be dispensed initially. The effects of inconsistent pre-pressure is best observed when a line of thermal barrier is deposited. If the pre-pressure of the thermal barrier material is too high, the thermal barrier material is first deposited as a splodge, before then becoming narrower and normal after that. If the pre-pressure of the thermal barrier material is too low, then the bead is too narrow at the start, before becoming wider and normal after that. In step 238, the robot 160 closes the nozzle valve 156 in the dispenser 114, thereby preventing any further thermal barrier material from being dispensed. Then in step 240, there is a delay lasting 0.1s or so (e.g. between 0.05 and 0.15 seconds), before step 242 then starts, in which the dispenser pumps are deactivated, and the dispenser pumps stop to convey the first and second materials 118a, 118b through the dispenser 114. Waiting 0.1s or so after closing the nozzle valve 156 before deactivating the dispenser pumps ensures the right pre-pressure of the thermal barrier material for the next dispense. At step 244, the dispenser 114 is at the bead end position. When the deposited bead is in the form of a continuous line of thermal barrier material, the bead end position may be different from the bead start position, whereas when the deposited bead is in the form of a drop of thermal barrier material, the bead end position may be the same as the bead start position. If further bead(s) are to be dispensed on the vehicle part, then the process moves to step 246 and then repeat steps 228 to 244 for the additional bead(s). Five beads may be dispensed for each vehicle part. Optionally, after the bead(s) are dispensed on the vehicle part, a sheet of flame retardant paper may be placed on top and pressed down using a flat plate, pushing the material into all of the cavities of the vehicle part and compressing the material into the correct locations within the vehicle part. Once all of the bead(s) have been dispensed on the vehicle part, the process moves to step 248. In step 248, the control system 170 uses the manifold pressure sensors in the manifold 152 to assess whether the pressure in the first and second channels of the manifold 152 is greater than a manifold pressure threshold. If the measured manifold pressures are lower than the manifold pressure threshold, the process moves onto step 252. However, if at least one of the measured inlet pressures exceeds the manifold pressure threshold, this means that there has been a big spike in pressure in the manifold 152 suggesting a blockage in the dispenser 114. In this case, the process moves onto step 250, where the control system 170 assigns the vehicle part as a reject. In step 252 (following either step 248 or step 250), the robot 160 is returned to its home position. In step 254 that follows, the movable platen is moved backdown from the guide rails, thereby lowering the vehicle part away from the dispenser 114 and the robot 160. Finally, in step 256, the vehicle part may be transferred away from the platen and out of the dispense station 116. This may be done e.g., by the transfer system and in particular the handling robot described above. If the vehicle part was rejected in step 250, the rejected vehicle part may be transferred to an inspection point where it is reworked and then re-inserted (e.g., by an 5 operator). Otherwise, the vehicle part may be transferred to e.g., another or the next station for further processing. It will be appreciated that various changes and modifications can be made to the present invention without departing from the scope of the present application. Reference numerals Feature Reference number Method 100 Steps of method 100 102 to 108 Container / barrel 110 Mixing chamber or static mixer 112 Dispenser 114 Dispense station 116 First and second material 118a, 118b Thermal barrier material system 120 Supply system 122 Mixing and dispensing system 124 Barrel-emptying unit or cabinet 130 Follower-plate 132 Main conduit or hose 134 Subsidiary conduit(s) 136 Foam pad(s) 138 Separator or insert 140 Pump chamber 150 Manifold 152 Nozzle 154 Nozzle or dispenser valve 156 Robot 160 Arm 162 Control system 170 Controller(s) 172 Processing means 174 Memory means 176 Input means 178 Output means 180 Method 200 Steps of method 200 202 to 256

Claims

1. An automated method of dispensing a compressible thixotropic thermal barrier material on a vehicle part, the method comprising:conveying a first material to a mixing chamber;conveying a second material to the mixing chamber;combining the first material and the second material to form the compressible thixotropic thermal barrier material in the mixing chamber, andactivating a dispenser to dispense the thermal barrier material on the vehicle part.

2. The method of claim 1, wherein, while the dispenser dispenses the thermal barrier material on the vehicle part, the dispenser is moved such that a continuous line of thermal barrier material is dispensed on the vehicle part.

3. The method of claim 1 or claim 2, further comprising a step of activating at least one positive displacement pump to convey the thermal barrier material from the mixing chamber to the dispenser.

4. The method of any preceding claim, wherein the dispenser comprises a dispenser valve arrangeable in a closed position, in which the dispenser valve prevents thermal barrier material being dispensed by the dispenser, and in an open position, in which thermal barrier material can be dispensed by the dispenser, and wherein activating the dispenser to dispense the thermal barrier material comprises arranging the dispenser valve in the open position.

5. The method of claim 4, wherein the dispenser valve is a ball valve.

6. The method of claim 4 or claim 5 when depending on claim 3, wherein activating the dispenser todispense the thermal barrier material comprises:waiting a first predetermined period after arranging the dispenser valve in the open position, and activating the at least one positive displacement pump.

7. The method of any of claims 4 to 6 when depending on claim 3, further comprising a step of deactivating the dispenser to cease dispense of the thermal barrier material, wherein the step of deactivating the dispenser comprises:arranging the dispenser valve in the closed position, waiting a second predetermined time, and deactivating the at least one positive displacement pump.

8. The method of claim 6 or claim 7, wherein the first predetermined period and / or the second predetermined period is between 0.05 and 0.15 seconds.

9. The method of any preceding claim, wherein the dispenser is only activated to dispense the thermal barrier material when a dispensing request is received.

10. The method of claim 9, further comprising a step of purging the thermal barrier material contained in the dispenser, and wherein the step of purging is performed when: a dispensing request has been received, and either there has been more than a third predetermined period since the dispenser last dispensed thermal barrier material on a vehicle part, or there has been more than the third predetermined period since the dispenser was last purged.

11. The method of any preceding claim, further comprising the or a step of purging the thermal barrier material contained in the dispenser, and wherein the step of purging is performed when either there has been more than a fourth predetermined period since the dispenser last dispensed thermal barrier material on a vehicle part or there has been more than the fourth predetermined period since the dispenser was last purged.

12. The method of claim 10 or claim 11, wherein the third predetermined period is between 4 and 6 minutes, and / or wherein the fourth predetermined period is between 55 and 65 minutes.

13. The method of any preceding claim, wherein the vehicle part is a vehicle battery subassembly.

14. The method of any preceding claim, wherein the thermal barrier material is a silicon paste comprisingpolymer microbubbles.

15. Computer readable instructions which, when executed by one or more processors, cause the one or more processors to perform the method according to any preceding claim.18

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