Abstract:
This invention relates to novel systems for testing guards closures or barriers used on hazardous machinery for personnel protection. The guards are tested separately or in conjunction with safety devices which may include interlocks, locking mechanisms and latching devices. The testing process proceeds without having to shut down the machine on which the guarding system is mounted. Testers are incorporated in the process for establishing the integrity of the safety devices and for executing self-testing. Also included are various novel devices that are unable in such systems.

Description:
FIELD OF THE INVENTION 
     This invention relates to the testing of various types of guard mechanisms for preventing access to a machine containing safety hazards. Such guard devices can exist alone or in conjunction with interlock mechanisms. 
     The guards are typically structural barriers that are locked in position and can consist of doors, gates, covers, latches and so forth. They will be variously referred to in this application by the synonymous terms, guards, closures and guard closures. In the usual situation the guards are not intended to be open and are only to be opened when the machine has come to a complete rest. When the guard is open it is intended that the machine has been shut down and will remain in the changed condition until the guard is closed even if there is an attempt to restart or restore the operating state of the machine at the main control box of the machine or from elsewhere. 
     BACKGROUND OF THE INVENTION 
     Guarding devices have long been used to prevent access to hazardous areas of machinery. Unfortunately there is a constant and continuous need to work on industrial equipment and every precaution must be taken to insure that prior to permitting a worker to work on the machinery the machine has come to a complete stop. It thus must be insured that the guards that are ever present to prevent entry into hazardous areas can not be opened to permit access until the machine has in fact come to a complete stop. 
     The present invention is directed to testing systems and mechanisms for insuring the integrity of the devices that indicate the status of machine operation so that guards may not be opened until the machine is completely shut down. Such devices are known as run down completion detectors which, when operating without fault, determine if the machine components within the hazardous space have stopped moving or not. Safeguarding systems include electrical and electronic components that consists of control and sensing systems with associated circuitry. In addition there are mechanical components that in addition to the guard closure include a lock and very possibly interlocks and run down completion detectors such as 1) motion detectors, 2) zero speed switches or detectors, 3) timing devices that are predicated on the fact that the run down times are known and can be relied upon 4) delay devices that also require that the machine components run down times can be relied upon and 5) interference devices that can be inserted in to the motion path of the machine components to insure that the machine has come to a complete stop. 
     In addition to the aforementioned devices to insure that the machine has come to a complete rest, mechanical interlocks or motion blockers can be inserted to absolutely prevent the machine from restarting until they are removed. 
     The current state of the art for testing the electrical and electronic components of the safeguarding systems is quite advanced. Commercial self testing systems are available which continuously or intermittently, remotely or proximally check for electrical/electronic faults in the system for single or multiple guard closures, during the running of the machine or when stopped, with the guard closures closed or open. If a fault is detected during the running of the machine, the machine is stopped. If detected during stoppage the machine can not restart until the fault is corrected. 
     However, the state of the art for testing mechanical components of the safeguarding systems is very primitive. For example the previously mentioned commercial self testing systems are not designed to detect failure or breakdown of the mechanical components of the safeguarding system while the machine is running. For mechanical failure or breakdown to be revealed to its electrical/electronic sensing system the mechanical exercising of the guard closure is required. There are currently no provisions or devices provided to exercise the mechanical components for testing purposes during running of the machine probably because such exercising would stop the machine. If the machine is stopped and the guard closure is opened then closed the electrical/electronic test systems will detect mechanical failures or breakdowns in the protective system. 
     There exists the obvious approach for testing the mechanical components mechanically by opening and closing each guard closure manually or automatically to determine if the machine is at rest when the guard closure is first unlocked, if power is interrupted whenever the guard closure is open, and if restart is allowed immediately upon reclosing. This is not a practical testing system, except in very restrictive circumstances, e.g. where there are few guard closures and generous amounts of time available for testing. 
     Accordingly, it appears to be very desirable that there be a test system for the mechanical testing of the mechanical components of safeguarding systems during running of the machine to detect if they have failed or not. Such systems to be most useful must be capable of testing the machine while it is running without stopping it. 
     In addition it would be desirable if the testing of the guards could be done in conjunction with the testing of the interlocks systems which are present on machines adjacent to guards to shut down machines when the guards are opened if the machine has not previously been shut down and prevents the resumption of powered operation of the machine while the guard is open. 
     Novel interlocks, interlock testing, testing systems and methods of testing have been extensively detailed in an application Ser. No. 08/861,328 now U.S. Pat. No. 5,870,317 entitled REMOTE AND PROXIMAL INTERLOCK TESTING MECHANISMS AND TESTING SYSTEMS filed in the names of the present inventors and assigned to the same assignee TRIODYNE INC. as the present invention. The filing date of said application is May 21, 1997 and is incorporated by reference into this application as setting forth in detail various interlock systems and methods of testing interlocks. A provisional application covering the same was filed on Mar. 3, 1997. 
     Referring again to the instant invention there are testing systems and apparatus for sensing the movement of a force displacement device applied as an opening force to the guard closure. The force of the displacement device may be constant or variable as the test situation demands. 
     The instant invention directs the testing of the guard closures and the testing of the interlocks to be performed during running of the machine and during the rundown phase of the machine when the machine is shut down. It does so without shutting the machine down due to the testing, as described in this submission and the previously referenced U.S. Pat. No. 5,870,317. This is done so, because for reasons of safety it is important to establish that during running of the machine and during its rundown phase, access is denied to the guard protected spaces containing running machine components, and that the interlocks provide the protection for which it has been designed. The guard closure and interlock testing methods, processes, devices and systems of the instant invention and in the U.S. Pat. No. 5,870,317 are designed to determine if that is the case, or if the case is that any specific guard closure and/or interlock have failed, hence no longer provide the expected protection. These are conditions which would be unknown without testing. 
     The overall system is illustrated by example, schematically in FIG  1 . Examples of a main routine for testing interlocks and guard closures is illustrated in FIGS. 8A,  8 B,  8 C and  8 D and various novel subroutines of testing systems for separate guard closures and in conjunction with closure and interlocking and closure testing mechanisms and systems as illustrated in FIGS. 2-7 and  9 - 15 . An overall description of applicants inventions are set forth under the following SUMMARY OF THE INVENTION and will be described in detail under the DESCRIPTION OF THE PREFERRED EMBODIMENTS. 
     SUMMARY OF THE INVENTION 
     The present invention includes a first novel system for testing a guard closure with a guard closure lock that is not protected by an interlock and includes the utilization of a program controller that will be connected up to a tester probe that can take various forms, which probe is to be mechanically moved to engage the guard closure. An example of a testing unit is set forth in FIGS. 9-11. The controller will be programmed to activate a guard closure test with the machine running and the guard closure lock allegedly latched. The first test will be to see if the probe will deploy so that the testing can take place. If the probe does not deploy, the guard closure cannot be tested and its failure will be so indicated at the program controller and will call for the scheduling of the necessary tester repair or replacement. If the probe does deploy then a sensor will indicate that the guard closure opens or is open or remains closed. If the guard closure is open the guard closure will have failed the test and if it is not open it will record that the guard closure passed the test. Following this test the probe will be retracted and the sensor will so advise the controller that the probe did retract or did not retract. If retraction of the probe did not take place the necessary repair and/or replacement will have to be scheduled to occur. If the closure passes all the tests it will be so indicated. If it did not pass all the tests there will be a suitable “test failed” warning indicator and depending on how the system is programmed, machine will be shut down or will be permitted to continue to run with the controller indicating the failures that did occur. If the machine shuts down, the guard closure testing system will be deactivated. If it is not shut down the program controller can be scheduled to continue to sequentially test a number of guard closures until the last guard closure is tested. At the completion of the testing of the last guard closure the guard closure test system will be deactivated. 
     The aforementioned system is an arrangement wherein the guard closure with its guard closure lock is tested and is not subsequently protected by interlocks. Another testing procedure that is an important aspect of the applicants invention is to be able to test interlocks of guards that are equipped with integral interlock-lock devices and which in a typical situation, when the guard is closed, will have the lock latched to the guard. For identification purposes this testing, procedure will be referred to as a second novel system FIGS. 3,  3 A,  3 B,  3 C and  3 D. 
     The integral interlock-lock is typically a device which houses both the interlock and the guard lock in a combined housing. The mechanical testing of the interlock for such a coupled device requires the unlatching of its lock from the guard before the interlock testing can be executed. 
     In this testing system before the interlock of a particular integral interlock-lock device is tested, the interlock function and the lock function is bypassed so that testing of the interlock and lock will not result in shutting down the machine. In this system a program controller will be activated to show that the testing process is to begin. This particular system will include a mechanism for unlatching the lock and if the lock unlatches by changing its state the change of state is indicated on the controller. If the lock did not unlatch then of course the interlock can not be tested and suitable indication will be made to show that the lock did not unlatch. In this particular situation if it is not desired to shut the machine down the controller will indicate that the guard latching system has to be repaired or replaced. The bypass functions will then be removed to reinstate the protection afforded by the interlock and lock. 
     Returning to the situation in which the lock did unlatch, the interlock tester will then be activated to move the interlock to its “guard open” position. It is to be noted again that various types of interlock testers and testing systems that would be acceptable in the instant system are discussed in great detail in the aforementioned U.S. Pat. No. 5,870,317 assigned to the assignee of the present invention which application is incorporated herein by reference. The details of the interlocks are not important to an understanding of the present invention except to note the following features of faultless interlocks. When an interlock is moved relative to the guard closure it protects, or vice versa, the interlock&#39;s sensing mechanisms changes state. When the interlock and guard closure are brought back together the interlock sensing system returns to its original state. The testing of the interlock is done by producing these relative displacements and determining if the required changes of state happen. 
     If the interlock fails to change its state to the “guard open” state by this test it will be recorded that the interlock failed the test and if it did change state the fact that the interlock passed the test will be recorded. 
     Since this system is used to test the interlock the interlock tester will as the next step restore the interlock to its “guard closed” position and will check if it has thereby returned to its “guard closed” state. If it failed to return to the “guard closed” state, recording of this will be made and if it did return the fact that the interlock passed the test will be so indicated. Following the aforementioned test the lock will be relatched and the system will be tested to check if the lock did relatch which would be to change its state back to what it was originally. If it did not return to its original state a recording to the effect that the lock failed to relatch will be made and if it did return the controller would indicate that the lock did relatch. Upon indicating that the lock relatched the bypassing of the lock in the system will be removed to restore its original protection. If the interlock passed all the tests this will be recorded, the interlock function will be restored by removing its bypass to restore its original protection and the program controller will sequentially test the interlocks of other integral integral-lock devices. If the interlock did not pass the tests the “test failed” warning indicators and devices will be activated and the machine may be shut down due to test failures and be repaired at that time, or not be shut down and just indicate what has occurred and continue to test other interlock-lock systems until the last one is tested at which time the program controller will be deactivated. 
     The present invention also includes a third novel system FIGS. 4,  4 A,  4 B,  4 C and  4 D comprising a guard closure test routine in which the closures are also protected by interlocks but wherein the locks and interlocks are not integral devices and the interlock is used to make a redundant closure test check. In this testing system one will first select a guard closure to be tested and reset the test routines to their test initiation states in which the guard closure locks are latched. Initially the interlock mechanisms are bypassed so that the testing of the guards will not shut down the machine in the event that the guard moves to the open position when a guard testing device such as a probe is used to attempt to open the guard closure. In addition to bypassing the interlocks “guard closure test on” indicators and devices are activated. As discussed in the earlier embodiment referred to as the first novel system the guard closure is tested by deploying a tester probe against the guard closure, and a program controller will indicate if the probe actually did deploy. If the probe did not deploy the test of this particular closure is terminated and the interlock function will be reinstated so that in the event the closure is opened the interlock will function normally, to turn off the machine. 
     A recording of the inactivity of the probe will be made and a suitable indicator will show that the guard cannot be tested and that necessary repair and/or replacement is required. If the probe did deploy then the amount of probe movement will indicate if the guard closure is closed, open or can be opened. An indication that the guard closure is in an open or opening condition will be recorded indicating that there is a problem with respect to the particular guard in question. If the guard closure is not opened this will be noted and if the interlock is known not to be faulty then the interlock will be used to make a redundant test check of the closure status. A known to be faulty interlock or one of unknown condition will not be used to make a closure test check. If it is indicated by the interlock that the guard is in the open position then the fact that the guard closure did fail the interlock test will be signaled. As the next test step, the closure tester probe is retracted and a test conducted to see if the probe did retract. Failure to retract will be recorded and replacement and/or repair will be scheduled. If the closure and probe passed all the tests the “test passed” indicators and devices will so indicate and the interlock function will be reinstated by removing the bypass to restore its original protection. Any failures will activate “test failed warning indicators and devices” and shut down the machine or not as desired and then move on to test another subsequent guard closure following the same method as herein aforesaid. 
     Another method of testing of allegedly locked guard closures which are also protected by interlocks can be done by a novel fourth system FIGS. 5 a ,  5   a - 1 ,  5   a - 2 ,  5   a - 3 ,  5   a - 4  and  5   b  calling for a sequential testing first of the interlock and then the closure. In this embodiment the test initiation states of the interlocks and guard closure test routines are reset and the appropriate indicators and devices are activated showing that the interlock and guard closure tests are being done. Also the interlock function is bypassed so that if the guard is opened by the guard closure test the interlock will not shut down the machine. The testing of the interlock will then be accomplished by changing, the interlock to the “guard open” position and then making the appropriate tests and records. If the interlock passes or fails the test this will be recorded and indicated. The interlock will then be restored by its tester to the “guard closed” position and checked if it has so returned. If it failed to return to the “guard closed” state, recording of this will be made and if it did return the fact that the interlock passed the test will be recorded. Following, the testing of the interlock the guard closure is tested in the same manner as set forth when discussing the novel third system. 
     Another system that could be employed is one that includes sequential testing of the interlock and then the closure where the allegedly locked closures are protected by an integral interlock-locking, device. This system embodies interlock testing as set forth in the previously described second system, the guard closure test from the previously described fourth system and the redundant closure test check by means of the interlock also from the previously described fourth system. 
     This fifth testing system FIGS. 6 a ,  6   a - 1 ,  6   a - 2 ,  6   a - 3 ,  6   a - 4 ,  6   b ,  6   b - 1 ,  6   b - 2  and  6   b - 3  includes a program controller that is initially programmed to bypass the interlock and lock function and activate the “tests on” indicators and devices and includes a locked guard closure. The interlock is tested by first unlatching the lock and testing if the unlatching did or did not occur. If it did not occur a record will be made of this and that the interlock cannot be tested. In this case the interlock will not be used to make a redundant closure test check since the interlock was not tested. 
     In the event the lock did unlatch by changing its state this system will test the interlock of the integral interlock-lock arrangement, as set forth in detail when describing the second system. Following the testing, of the interlock, the guard closure will be tested as set forth in the fourth system wherein a test device such as a probe is used with respect to a guard and its action tested and the interlock will be used to make a redundant closure test check if the interlock has been tested and if it had not failed the interlock tests. 
     This fifth system slightly differs from the fourth system since while the closure test probe may not deploy, which is a failure of the closure tester, and will be so recorded and indicated, the integral interlock-lock may pass all tests and thus provision is made to reinstate the interlock function by removing the interlock bypass and also the lock bypass to restore their protective functions and activate the “tests passed” indicators and devices. For all tests which did not pass, the “tests failed” warning indicators and devices will be activated and the program controller will so indicate, and a choice can be made to shut down the machine or allow the machine to operate while indicating what has occurred. 
     A sixth novel system FIGS. 7,  7 A,  7 B,  7 C and  7 D forming part of applicants invention is a routine for testing, allegedly locked closures protected by interlocks where there is a simultaneous testing of both the closure and the interlock with the same tester. The tester is so constructed that it performs the tasks of testing the guard closure and the interlock by the same action. In this system the interlock and/or tester is compliant base mounted as described in detail in the aforementioned pending, application that is incorporated herein by reference, but the tester and interlock are rigidly linked together. Prior to starting, one will select the interlock/guard closure to be tested and will reset their test routines to their test initiation states. Initially one will activate the “interlock/guard closure tests on” indicators and devices and bypass the interlock function and then test the guard closure and the interlock by deploying the tester probe to the guard closure and testing the closure and interlock. The steps of the test procedure and the action of the tester and its probe are best understood by reference to the descriptions of the flow chart in FIGS. 7,  7 A,  7 B,  7 C and  7 D and an exemplary mechanism in FIGS. 12-15. 
     In this sixth system, if the probe does not deploy then the guard and interlock cannot be tested, therefore the interlock function will be reinstated by removing the bypass to restore its protective function and the necessary repair and/or replacement will be scheduled. If the probe does deploy and the guard closure is open or has opened as determined by the amount of probe movement, it is recorded that the guard closure failed the probe test; if it did not open it is recorded that the guard closure passed the probe test. The program controller will then test to see if the interlock changed to the “guard open” state due to the action of the tester probe and it is determined if the interlock passed or failed this test and the outcome is recorded. The tester probe is then retracted and if the probe did or did not retract will be ascertained and it will be recorded and indicated whether the interlock passed or failed the retraction test. If the guard closure, interlock and probe passed all the tests the interlock fiction will be reinstated by removing its bypass to restore its protective functions and the “test passed” indicators will be activated. If all tests did not pass, the controller will activate the “tests failed” warning indicators and devices and shut down the machine or not as desired. If the machine is shut down the interlock function will be reinstated to restore its protective function and the “tests on” indicators deactivated. If it is elected to not shut down the machine the interlock will remain in the bypass mode and allow the machine to continue to operate and to schedule the necessary repair or replacements for a future time. 
     It remains to note that the novel systems illustrated and disclosed herein are employed as part of a main routine FIGS. 8A,  8 B,  8 C and  8 D that controls the running of a machine and also directs the testing of its guard closures and interlocks. The testing in question is done without shutting down the machine. This main routine is similar to that described in FIG. 2 for testing interlocks only of the referenced U.S. Pat. No. 5,870,317. 
     In addition to the various systems discussed above that can be used to test the guard closure either separately or in conjunction with interlocks it may be required to determine whether or not the machine has come to a complete stop before guard locks are allowed to unlatch and the guards are allowed to be opened. In such a situation it is usual to employ run down completion detection devices such as motion detectors, zero speed switches or detectors, timing devices, delay devices, interference&#39;s devices and motion blockers to make a final check if the machine has in fact come to a complete stop. Timing and delay devices are often used to assure that run down has resulted in zero motion by withholding a latch opening signal until the “worst case” or longest drift time has elapsed plus a safety factor. For machines that have a very broad range of stopping times, the “worst case” time may unduly compromise their utility. Here, it is often advantageous to use motion detectors and zero speed indicators to determine when machine components have come to rest. As a check on the veracity of zero motion devices, interference or motion blocking devices may be deployed before operators are allowed to open guard closures. Such devices may be as simple as setting a “dog into a gear” or a “stick into wheel spokes”. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the following drawings there will be a number of illustrations of systems for testing guards with or without interlocks as well as several mechanisms employed in such systems. 
     FIG. 1 is schematic view of an automatic guard closure and interlock testing system; 
     FIGS. 2,  2 A, and  2 B illustrate a flow diagram of a subroutine for testing closures not protected by interlocks; 
     FIGS. 3,  3 A,  3 B,  3 C and  3  D illustrate a flow diagram of a subroutine for testing interlocks of guards equipped with integral interlock-lock devices; 
     FIGS. 4,  4 A,  4 B,  4 C and  4 D illustrate a flow diagram of a guard closure test subroutine for closures protected by interlocks; 
     FIGS. 5 a ,  5   a - 1 ,  5   a - 2 ,  5   a - 3 ,  5   a - 4  and  5   b  illustrate a flow diagram of a subroutine for the sequential testing of interlocks and closures; 
     FIGS. 6 a ,  6   a - 1 ,  6   a - 2 ,  6   a - 3 ,  6   a - 4 ,  6   b ,  6   b - 1 ,  6   b - 2  and  6   b - 3  illustrate a flow diagram of a subroutine for the sequential testing of interlocks and closures including an integral interlock-locking device; 
     FIGS. 7,  7 A,  7 B,  7 C and  7 D illustrate a flow diagram of a subroutine for the simultaneously testing of both the closure and an interlock with the same tester; 
     FIGS. 8,  8 A,  8 B,  8 C and  8 D illustrate an example of a main routine for testing interlocks and guard closures; 
     FIGS. 9-11 illustrate various positions of an embodiment including an assembly for testing a guard closure normally locked in position; 
     FIGS. 12-15 illustrate various positions of a second embodiment for testing a guard closure and an interlock in which the closure tester is connected to a interlock assembly that is in turn secured to a complaint base. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring first to FIG. 1 the testing system  10  preferably includes one or more machines  11  (one being shown), a control unit  14 , an input device  16 , and an output device  18 . The system  10  may also include one or more detection units (one being shown) such as, for example, flow sensors, proximity sensors, heat detecting devices, to detect certain operating conditions of the system  10 . The detection units  20  of the system  10  may communicate with the control unit  14  by transmission line or any other suitable communication link. It will be recognized that the control unit  14 , the input device  16 , and output device  18  may be integral with the machine  11  or remote from the machine  11 . 
     The schematic illustration of the machine  11  pictures an arrangement wherein each guard  15  can be protected by an interlock  12   a ,  12   b  etc. Each interlock has a switch and may be in communication with or coupled to the control unit by transmission lines  13   a ,  13   b  etc. respectively. The transmission lines may be one-way on bi-directional communication links of any suitable type. 
     The system can employ an integral locking mechanism L or a separate locking device S schematically shown mounted on each guard in FIG. 1 can be provided if desired. Similarly, while interlocks are shown in conjunction with guard closures a number of the closures may not be protected by interlocks. Thus the testing system is not intended to limit the application of applicants invention and is merely intended to provide a general overview of systems that can be employed. 
     The control unit can be set to test the guards and/or interlocks on any specified schedule, for instance, during each shift, hourly, daily, weekly, or any other interval. A signal or warning indicator, such as a light or flag, can be placed wherever desired, for instance, adjacent to each guard, and be suitably activated in the event the guard and/or interlock fails, to warn personnel of this condition. 
     In FIG. 1, the input device  16  of the system  10  is in communication with or coupled to the control unit  14 . The input device  16  may include a keyboard, a keypad, or any other suitable input device  16 . The input device  16  may allow a number of versatile control or scanning functions to be utilized. For example, the guards and interlocks may be continuously monitored or checked at a preselected time. Alternatively, the frequency and duration of monitoring all or a selected number of guards and interlocks may be initially preset and/or changed. 
     The output device  18  of the system  10  is also in communication with or coupled to the control unit  14 . The output device  18  may generate a message or an alarm that can be visual, audio, or whatever else is suitable, singly or in combination, when a malfunctioning guard or interlock is detected. The output device  18  may include a display or monitoring panel that may alert an operator that a trouble or an alarm condition exists and may also indicate the location of the malfunctioning interlock in the environment. 
     The output device  18  may further display a message to identify what is being tested and where, what is bypassed for testing and what is not, etc. and the corrective action required. The output device  18  may be designed at any level of sophistication or complexity in order to process the information about the status of the guards and interlocks and to indicate that a problem exists with one or more guards or interlocks. 
     The control unit  14  of the system  10  checks the functioning or operation of one or more guards or interlocks as well as other machine controls. The control unit  14  may include, for example, a program unit, a processing unit, a computer, a programmable logic controller, a microprocessor, etc. The control unit  14  can be commanded with any suitable operating system, and can be digital, analog, hardwired, etc., or combinations of these. The control unit  14  can be commanded to continuously monitor the guards and interlocks and test them in any sequence combination at a preselected schedule, frequency, duration, or randomly. 
     When the control unit  14  detects a malfunctioning guard or interlock, a light and/or any other suitable alarms may be activated at the output device  18  and/or near the interlock, and the control unit  14  may place the guard or interlock in a maintenance standby mode as further described below. A message indicating a malfunctioning guard or interlock may also be displayed on the output device  18 . The particular location of the guard or interlock of the machine  11  may further be identified. 
     We turn now to the subroutines used for testing guards and or interlocks. FIGS. 2-8 illustrates test routines executed by the program controller unit to test; A) individual guard closures; B) interlocks of guards equipped with integral interlock-locking devices C) guards protected by interlocks; D) guards protected by interlocks wherein there is sequential testing of first the interlock and then the guard; E) guards protected by integral interlock-lock devices whereby there is sequential testing of the interlock then the guard; F) testing of guards protected by interlocks calling for simultaneous testing of the guard closure and the interlock with the same testing device and G) an example of a main routine for the testing of interlocks and guard closures. The interlock and guard test routines may be implemented by conventional hardware components and circuit designs, computer programming, and combinations thereof. Exemplary flow chart diagrams are described below, but it is understood that these are merely for the purposes of illustration implementation that will carry out the functions of the process. 
     Interlock testers, testing systems and methods of testing have been extensively detailed in U.S. Pat. No. 5,870,317 entitled Remote and Proximal Interlock Testing Mechanisms and Testing Systems filed in names of the present inventors and assigned to the same assignee Triodyne Inc. as the present invention. All interlock testing referred to here can be executed and accomplished by such testers, methods and systems. 
     Starting with FIGS. 2A and 2 B there is shown a subroutine to test a guard closure that is not protected by interlocks. The subroutine is designated by the number  30  and is started by selecting a guard closure to be tested wherein the memory location storing the test states of the closure is reset at  30 A. At  30 B the guard closure “test on” indicators and devices are activated. To test the position of the guard closure a tester probe is applied to the guard closure at  30 C and at  30 D a determination is made whether the probe deployed, and if it deploys does it open the guard closure or indicates that the guard closure is open at  30 E. If the probe did not deploy it will be so recorded at  30 F. At  30 G the indicators will show that the probe did not deploy and the guard cannot be tested and the necessary repair and/or replacement will be scheduled at  30 H. 
     Returning now to the indicator  30 E where if the guard closure opened or is open then at  30 J it will be recorded that the guard closure failed the test. If the guard did not open then at  30 I it is recorded that the guard closure passed the test. Following the test the closure tester probe is commanded to retract from the closure at  30 K. From there it will be determined at  30 L if the probe retracted, and if it retracted it will be determined at  30 M whether the closure and probe passed all the tests. If the probe did not retract this will be recorded at  30 N and at  30 P indicators will show that the probe did not retract. At  30 Q the necessary tester repairing and/or replacement will be scheduled. Returning now to  30 M wherein it is determined if the closure and probe did or did not pass all the tests there are two possible results. If they did not pass all the tests, the test failed warning indicating devices are activated at  30 R and at  30 S it will be determined whether the machine is to be shut down or not due to the test failures. If yes, the machine is shut down at  30 T and if the machine is not to be shut down at  30 U the necessary repair and/or replacements are scheduled. If the machine is shut down the guard closure test indicator devices will be deactivated at  30 V after which there is a return to the main routine shown in FIGS. 8A,  8 B,  8 C and  8 D. The main routine is described in detail hereinafter. If the path is from  30 U to  30 W and if it is the last guard closure to be tested as indicated at  30 W the system is then deactivated at  30 X and returns to the main routine but if not the testing process will be started over again at a new guard closure. If the closure and probe passed all the tests it will be indicated at  30 Y. 
     We, next go to FIGS. 3A,  3 B,  3 C and  3 D which schematically illustrates the testing of interlocks of guards equipped with integral interlock-locking devices. 
     The integral interlock-lock is typically a device which houses both the interlock and the guard lock in a combined housing. The mechanical testing of the interlock for such a coupled device requires the unlatching of its lock from the guard before the interlock testing can be executed. This test subroutine  40  has the option of shutting down the machine due to test failures or put the interlock and/or lock in a bypass mode thus allowing the machine to continue to operate and subsequently test other interlock-locking devices if desired. It will also indicate and/or schedule the necessary repair or replacement of the failed devices. 
     Referring now in detail to the FIGS. 3A,  3 B,  3 C and  3 D flow chart when this subroutine  40  is initiated the memory location storing the test states of the interlock and lock to be tested is reset at block  40 A. It will be recognized that the memory location for a single interlock-lock device may be reset or the memory location for all interlock-lock devices may be reset. Next the system is set to bypass the lock function at  40 B, bypass the interlock function at  40 C and activate the “test on” indicators and devices at  40 D. The next step is to unlatch the lock at  40 E and if the lock did unlatch (change state) at  40 F the interlock tester at  40 G will change the interlock to the “guard open position” and test it. If the lock did not unlatch this will be recorded at  40 H and indicate that the interlock can not be tested and the lock and interlock functions will be reinstated at  40 I. Indicators will be activated at  40 J to inform that the lock did not unlatch and that the interlock can not be tested. Scheduling of necessary lock repair and/or replacement will be signaled at  40 K. 
     Returning now to  40 G where the interlock was changed to the “guard open” position and tested we will move to  40 L which will indicate whether or not the interlock changed to the guard open state. If it did not at  40 M it will be recorded that the interlock failed the test. If the interlock passed the test  40 N will record this occurrence. The interlock tester restores the interlock to the “guard closed” position where it is tested at  40 U. At  40 V it is determined if the interlock it returned to the “guard closed state”. If not it will record that the interlock failed the test at  40 W and if it passed the test a record is made at  40 X. In both instances the system proceeds to  40 P where the lock will be commanded to be relatched and tested. At  40 Q there will be a test to determine if the lock did change its state and thus relatched. At  40 R it will record if the lock failed the test and if the lock relatched it will be recorded at  40 S and the lock function will be reinstated at  40 T by removing the bypass. If the interlock and lock passed all the tests as indicated at  40 Y the interlock function will be reinstated by removing its bypass at  40 Z and the “test passed” indicator and devices will be activated at  40 AA. If the interlock and lock did not pass all the tests, the test failed warning indicator devices will be activated at  40 BB and then one may choose to shut down the machine due to test as failures indicated at  40 CC by shutting down the machine at  40 DD. The machine shut down is followed by the reinstating of the bypassed functions at  40 HH and by the deactivation of the “tests on” indicators and devices at  40 II. If the choice at  40 CC is that one does not want the machine to shut down then at  40 EE the interlock and/or lock will be left in the bypass mode allowing the machine to continue to operate and schedule necessary repair or replacement of the failed devices. If it is the last interlock tested as indicated at  40 FF the test and indicators will be deactivated at  40 GG which returns the system to the main routine. If additional interlocks/locking devices are to be tested the routine returns to  40 A and starts the testing again for another interlock-lock device. 
     In FIGS. 4A,  4 B,  4 C and  4 D there is illustrated a guard closure test subroutine for closures that are protected by interlocks. The subroutine is designated by the number  50 . In starting the system, the memory for the guard closures to be tested is reset to the proper test states at  50 A. Following this the interlock function is bypassed at  50 B and the guard closure test indicators and devices are activated at  50 C. The guard closure is then tested at  50 D by applying a tester probe to the guard closure. At  50 E it is determined whether or not the probe deployed. If the probe did not deploy the interlock function will be reinstated by removing the bypass and at  50 F and it is recorded at  50 G that the probe did not deploy and the guard cannot be tested. At  50 H activated indicators will be showing that the probe did not deploy and that the guard cannot be tested, following which at  50 J the necessary tester repair and/or replacement will be scheduled. 
     Returning to the indicator  50 E, if the tester indicates that the probe did deploy the next test is at  50 K where it is determined if the guard closure did open or is opened by the probe. If the closure did open or is opened  50 L will record that the guard closure failed the probe test. If the guard closure is not open and did not open  50 M will record that the guard closure passed the test. The next step is to use the interlock to make a redundant closure test check. At  50 P there will be an indication as to whether or not the interlock is known not to be faulty and if the interlock is not known not to be faulty  50 Q will indicate that the interlock is not to be used to make a redundant closure test check. If the interlock is known not to be faulty the interlock is used to make a redundant closure test check at  50 R. The interlock state is then determined at  50 S. If the closure test changed the interlock to the “guard open” state,  50 T will indicate that the guard closure failed the redundant interlock check test. If at  50 S the interlock did not change to the “guard open” state  50 U will indicate that the guard passed the redundant interlock closure test. The paths from  50 U,  50 Q,  50 T and  50 L all lead to  50 V where the closure tester probe is commanded to retract from the closure and its retraction status is tested at  50 W. If  50 W indicated that the probe did retract then at  50 X it will be determined that the closure and probe passed all tests. If the probe did not retract it will be recorded that the probe did not retract at  50 Y and the indicators at  50 Z will show that the probe did not retract and the necessary tester repair and/or replacement will be scheduled at  50 AA. 
     If the closure and probe did pass all the tests at  50 X the “test passed” indicators and devices are activated at  50 BB and the interlock function is reinstated at  50 CC by removing the bypass. If the closure and probe did not pass all of the tests the test failed warning indicators and devices will be activated at  50 DD and a selection at  50 EE will be made to shut down the machine due to test failures by shutting down the machine at  50 FF or choose not to shut down the machine and put the interlock in the bypass mode at  50 GG to allow the machine to continue to operate and schedule necessary replacements of the failed devices. If it is the last closure to be tested as indicated at  50 HH the guard closure test indicators and devices will be deactivated at  50 II and the system returns to the main routine. If at  50 HH it is determined that it is not the last guard closure to be tested, then the testing process will start all over with the next scheduled guard closure by returning to  50 A. If the machine is shut down at  50 FF, then it is followed by the reinstating of the bypassed interlock function at  50 LL and by the deactivation of the “guard closure test on” indicators and devices at  50 MM. 
     In FIGS. 5 a - 1 ,  5   a - 2 ,  5   a - 3 ,  5   a - 4  and  5   b  there is illustrated a guard closure test subroutine  60  for closures protected by interlocks wherein there is sequential testing of first the interlock and then the closure. When starting the system the memory for the interlock/guard closure to be tested is reset to the proper states at  60 A. Following this the interlock function is bypassed at  60 B and the “interlock/guard closure tests on” indicators and devices are activated at  60 C. The next step is to test the interlock which is shown in FIG. 5 b  wherein at  60 D the interlock tester is used to change the interlock to the “guard open” position. At  60 E it will be determined if the interlock did change to the “guard open” state and if it did not it will be recorded that the interlock failed the test at  60 F or that it passed at  60 G. Then at  60 H the interlock tester acts to restore the interlock to the “guard closed” position and tests it. At  60 I it will indicate whether or not the interlock returned to the “guard closed” state. If it did not, a record that it failed the interlock test will be made at  60 J or that the interlock passed the test at  60 K. Following this, the guard closure is to be tested and reference is now made again to FIG. 5 a - 2  wherein at  60 L the guard closure is tested by applying a tester probe to the guard closure. At  60 M it is determined whether or not the probe deployed. If the probe did not deploy the interlock function will be reinstated by removing the bypass at  60 N and at  60 P it is recorded that the probe did not deploy and the guard cannot be tested. At  60 Q activated indicators will reflect that the probe did not deploy and that the guard cannot be tested. Following at  60 R the necessary tester repair and/or replacement will be scheduled and the program controller will index to test the next interlock/closure at  60 S. 
     Returning now to  60 M where if it has been indicated that the probe did deploy, the next test is at  60 U where it is determined if the guard closure did open or is opened by the probe. If the closure did open or is opened which should not have been the case  60 V will record that the guard closure failed the probe test. If the guard closure is not and did not open  60 W will record that the guard closure passed the test. The next step is to use the interlock to make a redundant closure test check. At  60 X there will be an indication as to whether or not the interlock passed the test and if it did not  60 Y will record that the interlock is not to be used to make a redundant closure test check. If the interlock did pass the test the interlock is used to make the redundant closure test check at  60 Z and at  60 AA it will be tested to see if the interlock changed to a “guard open” state. If the closure test changed the interlock to the “guard open state”  60 BB will indicate that the guard closure failed the interlock test. If at  60 AA the interlock did not change to the “guard open” state,  60 CC will indicate that the guard closure passed the interlock test. The paths from  60 CC,  60 Y,  60 BB, and  60 V all lead to  60 DD where the closure tester probe is commanded to retract from the closure as indicated at  60 DD and its retraction status is determined at  60 EE. If  60 EE indicates that the probe retracted, then at  60 FF it will be determined if the closure, interlock and probe did or did not pass all tests. If the probe did not retract it is recorded that the probe did not retract at  60 GG and indicators at  60 HH will show that the probe did not retract and the necessary test repair and/or replacement will be scheduled at  60 II. The process then proceeds to  60 FF. 
     If the closure and probe did pass all the tests at  60 FF, test passed indicators and devices are activated at  60 JJ and the interlock function is reinstated at  60 KK by removing the bypass. If the closure and probe did not pass all of the tests the “test failed” warning indicators and devices will be activated at  60 LL. Subsequently, a selection can be made at  60 NN to shut down the machine due to test failures by shutting down the machine at  60 NN. After shutting down the machine the interlock function will be reinstated at  60 PP and testing is deactivated at  60 QQ and the process returns to the main routine shown in FIGS. 8A,  8 B,  8 C and  8 D. If the choice is made not to shut down the machine the interlock is put in the bypass mode at  60 RR to allow the machine to continue operating and schedule necessary replacements of the failed device. If it is the last closure to be tested as indicated at  60 S the interlock/guard closure test indicators will be deactivated at  60 SS and the process returns to the main routine shown in FIGS. 8A,  8 B,  8 C and  8 D. If not the process will be repeated for testing another closure protected by an interlock. 
     We turn now to an additional novel embodiment of applicant&#39;s invention as shown in FIGS. 6 a - 1 ,  6   a - 2 ,  6   a - 3 ,  6   a - 4 ,  6   b - 1 ,  6   b - 2  and  6   b - 3 . Here the guard closure is protected by an integral interlock-lock, the testing of which was described in FIGS. 3A,  3 B,  3 C and  3 D. When this subroutine  70  is initiated the memory location storing the test states of the interlock-guard closure to be tested is reset at  70 A. It will be recognized that the memory location for a single location for a single interlock-lock may be reset or the memory location for all interlock-lock devices may be reset. 
     Initially, the system is set to bypass the lock function at  70 B, bypass the interlock function at  70 C and activate the “test on” indicators and devices at  70 D. 
     Reference is now made to FIGS. 6 b - 1 ,  6   b - 2 , and  6   b - 3  wherein a system is shown for testing the interlock which by way of reference is similar to FIGS. 3A,  3 B,  3 C and  3 D. In this arrangement the first step is to unlatch the lock at  70 E. If he lock did unlatch change state at  70 F the interlock tester at  70 G will be commanded to change the interlock to the “guard open position” and test it. If the lock did not unlatch this will be recorded at  70 H and it will be indicated that the interlock cannot be tested. The lock and interlock functions will be reinstated at  70 I and indicators will be activated at  70 J to inform that the lock did not unlatch and thus the interlock cannot be tested. Scheduling of necessary lock repair and/or replacement will be signaled at  70 K. Following this the guard closure is to be tested and reference is made to B on FIG. 6 a - 2 . 
     However, as aforementioned this system provides for testing the interlock which is done if the lock did unlatch. To this end we return to  70 G wherein the interlock tester is used to change the interlock to the “guard open” position and test for its change of state. 
     At  70 L there would be an indication of whether or not the interlock changed to the guard open state and if it did not at  70 M it will record that the interlock failed the test. If the interlock passed the test  70 N will record this occurrence. The interlock tester restores the interlock to the “guard closed” position where it is tested at  70 U. At  70 V it is determined if the interlock returned to the “guard closed state”. If it did not it will be recorded that the interlock failed the test at  70 W and if it passed the test a record is made at  70 X. 
     In either instance the system proceeds to  70 P where the lock will be commanded to be relatched and tested. At  70 Q there will be a test to determine if the lock did change its state and thus relatch. At  70 R it will record if the lock failed the test. If the lock relatched it will be recorded at  70 S that it passed the test and the lock function will be reinstated by removing the bypass at  70 T. 
     Following the recording of all passed or failed tests the system returns to test the guard closure at item B in FIG. 6 a - 2 . 
     The system for testing the guard closure in FIGS. 6 a - 1 ,  6   a - 2 ,  6   a - 3  and  6   a - 4  is similar to that which has been set forth in FIG. 5 a . Specifically, at  70 AA the guard closure is tested by applying a tester probe to the guard closure. At  70 BB whether or not the probe deployed is determined. If the probe did not deploy then at  70 CC it is recorded that the probe did not deploy and the guard cannot be tested. At  70 DD activated indicators will reflect that the probe did not deploy and that the guard cannot be tested. Following at  70 EE the necessary test or repair and/or replacement will be scheduled and if at  70 FF it is determined that the interlock testing was not performed the program will index at  71 C to test the next interlock/closure. If the interlock-lock testing was performed as indicated at  7 OFF and it passed as determined at  70 CD, then at  7 OGG (item C) is where the interlock function is reinstated and the “tests passed” indicators are activated. If the interlock-lock did not pass its test then this will be suitably indicated at  70 CD and the program will proceed to  70 XX, (item D). 
     Returning now to  70 BB where if it has been indicated that the probe did deploy the next test is at  70 HH where it is determined if the guard closure did open or is opened by the probe. If the closure is open or is opened, which should not have been the case,  70 II will record that the guard closure failed the probe test. If the guard closure is not opened  70 JJ will record that the guard passed the test. The next step is to use the interlock to make a redundant closure test check. At  70 KK there will be an indication as to whether or not the interlock passed the test and if it did not  70 LL will record that the interlock is not to be used to make a redundant closure check. If the interlock did pass the test the interlock is used to make the redundant closure check at  70 MM and at  70 NN it will be tested to see if the interlock changed to a “guard open state”. If the closure test changed the interlock to the “guard open” state  70 QQ will indicate that the guard closure failed the interlock test. If at  70 NN the interlock did not change to the “guard open” state  70 PP will indicate that the guard closure passed the interlock test. The paths from  70 PP,  70 LL,  70 QQ and  70 II all lead to  70 RR where the closure tester probe is commanded to retract from the closure as indicated at  70 RR. If the probe retracted or not it would show at  70 SS. If the probe did retract, then at  70 TT it will be determined if the closure, the interlock-lock and probe passed all tests. If the probe did not retract it is recorded that the probe did not retract at  70 UU and indicators at  70 VV will show that the probe did not retract and the necessary repair and/or replacement will be scheduled at  70 WW. The process then proceeds to  70 TT. 
     If the closure, interlock-lock and probe all passed their tests “test passed” indicators and devices are activated and the interlock function is reinstated at  70 GG by removing the bypass. If the closure, interlock-lock and probe did not all pass their tests, “test failed” warning indicators and devices will be activated at  70 XX. Subsequently a selection is made at  70 YY to either shut down the machine due to test failures at  70 ZZ after which the interlock function is reinstated and testing indicators are deactivated at  71 A and the process returns to the main routine shown in FIGS. 8A,  8 B,  8 C and  8 D, or the selection is made to not shut down the machine and put the interlock and/or lock in the bypass mode at  71 B to allow the machine to continue operating and schedule necessary repair or replacement of the failed device. If it is to be the last closure tested as indicated at  71 C the “tests on” indicators will be deactivated at  71 D and the process returns to the main routine shown in FIGS. 8A,  8 B,  8 C and  8 D. If there are more to be tested the process will be repeated starting at the beginning to test another closure integral interlock-lock device. 
     A novel sixth system FIGS. 7A,  7 B, &amp;  7 C and  7 D illustrate a guard closure test subroutine for testing a closure protected by interlocks. In this system there is simultaneous testing of both the closure and the interlock by using the same tester. The interlock and/or the tester are compliant base mounted for this purpose which makes this approach possible. As previously mentioned the operation and structure of various types of interlocks mounted on a compliant base, interlock testers, test systems and test methods for such is discussed in detail in the aforementioned U.S Pat. No. 5,870,317. In essence the interlock will be bypassed and the guard closure and the interlock will be tested by deploying the tester probe to the guard closure and if the closure is locked and cannot be opened the interlock will retract and thus can change state, thereby permitting the testing of the interlock, and if the closure opens in response to the tester the interlock member will be tested due to its freedom to move upon opening of the closure which move again permits the interlock to change state. 
     FIGS. 7A,  7 B,  7 C and  7 D is a flow chart illustrating the components of this system  80 . At  80 A the program test states of the interlock/guard closure to be tested are reset. At  80 B the interlock function is bypassed and at the same time at  80 C the “interlock/guard test on” indicators and devices are activated. Following this the guard closure and interlock are tested at  80 D wherein the tester probe is moved to engage the guard closure and test the closure and interlock. At  80 E it will be determined if the probe deployed and if it did not the interlock function will be reinstated at  80 F and the fact that the probe did not deploy and that the guard and interlock cannot be tested is recorded at  80 G. Indicators at  80 H inform that the probe did not deploy and that the guard and interlock cannot be tested following which the necessary tester repair and/or replacement will be scheduled at  80 I. Next, the process moves to  80 J and acts to test another interlock/guard closure or if this is the last closure to be tested the “test on” indicators will be deactivated at  80 K and the process returns to the main routine shown in FIGS. 8A,  8 B,  8 C and  8 D. If the probe did deploy at  80 E then at  80 M there is a determination if the guard closure opened upon being acted upon by the probe or is open. If the guard closure is opened or is open there will be a record made that it failed the probe test at  80 N and if the guard closure did not open it will be recorded that the guard closure passed the test at  80 P. 
     If the probe has moved the guard to the open position the interlock is free to move and thereby change to the “guard open” state, and at  80 Q it is determined if it did so. If the interlock changed state it will be indicated that the interlock passed this test at  80 S or if it did not change state the test failure is indicated at  80 R. At  80 T the tester probe is commanded to retract from the closure and at  80 U there will be a determination as to whether or not the probe did retract. If the probe retracted the process moves to  80 V. If the probe did not retract a record of this is made at  80 W and indicators will activate at  80 X indicating that the probe did not retract, upon which the necessary repair and/or replacement will be scheduled at  80 Y and the process proceeds to  80 V. 
     Returning now to  80 V if the interlock did not return to the “guard closed” state a record that the interlock failed the test will be made at  80 AA and if it passed the test at  80 BB. Then at  80 CC there will be a determination whether the closure, interlock and probe passed all their tests and if they did then at  80 DD the interlock function is reinstated by removing the bypass and  80 EE will indicate that all tests have been passed. If the closure, interlock and probe did not pass their tests then the test failed warning indicator will be activated at  80 FF and then at  80 GG a decision is made whether to shut down the machine or not due to test failures. If the machine is shut down that will be done at  80 HH and following that the interlock/guard closure test indicators and devices will be deactivated at  80 II and the interlock function will be reinstated at  80 JJ, and the process returns to the main routine of FIGS. 8A,  8 B,  8 C and  8 D. 
     If the closure is not to be shut down then as shown at  80 KK the interlock continues to be in the bypass mode which allows the machine to continue to operate and the necessary repair and/or replacement of the failed devices will also be scheduled at  80 KK. Following this, it is determined at  80 J if a new interlock/closure will be tested or if it is the last closure to be tested, then the interlock/guard closure test indicators will be deactivated at  80 K and the process returns to the main routine of FIGS. 8A,  8 B,  8 C and  8 D. 
     FIGS. 8A,  8 B,  8 C and  8 D illustrate a main routine  90  which controls the running of a machine and also directs the testing of its guard closures and interlocks by means of the set of subroutines of FIGS.  2 - 7 . The main routine  90  is similar to that described for FIGS. 2A and 2B for testing interlocks only of the referenced U.S. Pat. No. 5,870,317. 
     The main routine  90  directs the testing of the closures and the testing of the interlocks to be performed during running of the machine and during the rundown phase of the machine when the machine is shut down. It does so without shutting the machine down due to the testing, as described in this submission and the previously referenced U.S. Pat. No. 5,870,317. For reasons of safety, it is important to establish that during running of the machine and during its rundown phase, access is denied to the guard protected spaces containing running machine components, and that the interlocks provide the designed for protection. The guard closure and interlocks testing methods, processes, devices and systems of this instant invention and in the U.S. Pat. No. 5,870,317 are designed to determine if that is the case, or if the case is that any specific guard closure and/or interlock have failed, hence no longer provide the expected protection. These are conditions which would be unknown without testing. 
     The control unit  90 A of the machine system may process all input and outputs, monitor all switches, and determine whether the machine is operating properly. The main disconnect may be opened or closed at block  90 B and it will be determined at  90 C whether the main disconnect is opened or closed. If it is not closed the machine will be turned off at  90 D. If the main disconnect is closed then the start/stop controls will be queried at  90 F and it will be determined at  90 F if the control is in the start position. If the control is not in the start position the machine will be turned off at  90 G. The emergency or other stop controls will be activated or deactivated at  90 H and at  90 I it will be determined if the stop controls have been activated or not. If the stop controls have been activated the machine is turned off at  90 J and after the machine motion has stopped the guards will be unlocked if required at  90 K. If the stop controls are not activated it will be determined if the input/output (I/O) controls are enabled at  90 L. If they are not enabled it will be so indicated at  90 M. If the controls are enabled there will be a determination at  90 N if the machine controls other than the interlocks are satisfied. If they are not the machine will be turned off at  90 P and after the machine motion has stopped the guards will be unlocked if required at  90 Q before returning to the main system control unit at  90 A. 
     If the machine controls other than the interlocks are satisfied there will be a determination at  90 R as to the satisfaction of the interlock sensor states. For any interlock whose sensor states are not satisfied it will be determined at  90 S if its interlock/lock bypass has been enabled by the interlock test subroutine when the interlock was tested. If the interlock bypass has not been enabled, the machine will be turned off at  90 P. If the bypass is enabled at  90 S, or the interlock sensor states are satisfied at  90 R, then at  90 T it will be determined if the interlock and/or the guard testing is in progress. If the testing is in progress there is a return to the machine control system at  90 A. If the testing is not in progress the determination will be made at  90 U if the machine is running. If the machine is running a determination is made at  90 V whether or not to shut down the machine. If the machine is not to be shut down it will be determined at  90 W if the interlock and/or guard tests are to be initiated. If they are to be initiated and conducted, they are performed at  90 Y by utilizing the appropriate test subroutine from the sets illustrated by FIGS. 2-7. In parallel with the testing initiation, control is returned at  90 X to the machine system&#39;s main control unit  90 A, so that the machine can be checked and kept under control while the testing is in progress. If at  90 V it is determined to shut down the machine, the machine run down phase will be initiated at  90 Z and the interlocks and guards will be tested at  90 W during this rundown phase by utilizing the appropriate test subroutine from the sets illustrated by FIGS. 2-7. In parallel with the testing initiation, control is returned at  90 X to the machine system&#39;s main control unit  90 A, so that the machine can be checked and kept under control while the testing is in progress. After completing the tests at  90 Y a determination is made at  90 AA if the test subroutine at  90 V shut the machine off. If the subroutine at  90 Y did not shut off the machine, then  90 AA returns to the machine&#39;s main control unit  90 A. If the subroutine  90 Y did shut off the machine, then  90 AA branches to  90 BB where after the machine motion has stopped the guards will be unlocked if required. 
     To complete the description of the system we return to  90 U and discuss what occurs if it has been determined that the machine is not running. If it is determined at  90 CC that the machine is not running the guards will be closed and locked to enable machine startup. Following this at  90 DD it will be decided whether to start the machine or not. If the decision at  90 DD is not to start the machine then the control branches to  90 P, the “machine off” status. If the decision is to start the machine, then the machine&#39;s running status is determined at  90 EE. If running, the control branches to  90 W. If not running then control branches again to  90 P, the machine off status. 
     Referring now to FIGS. 9-15 there are illustrated various embodiments of structures that can be used when testing the status of guard closures alone or combined with interlocks. These are but two examples of a wide variety of mechanisms that can be employed. 
     The testing of the guard closures is to be performed when their status is supposed to be “the guard closure is closed and cannot be opened”. This is the case during running of a machine when the closure is meant to prevent the access to a space containing the hazards of running machine components or other hazards. It is also the case when the machine is shut down and the protected machine components are running down to zero speed. 
     FIGS. 9,  10  and  11  illustrate the working of a force displacement type device using a probe for testing the position status of a guard closure. In this embodiment the closure tester is separate from an interlock arrangement but it can be appreciated that an interlock device separate from the tester as well as a device for testing the interlock may be present if desired. In FIGS. 9,  10  and  11  a lock is provided to keep the guard closure latched closed while the closure is in its hazard protective status. In the subject arrangement the test determines whether the guard closure opens or not due to the test or whether it is found in the open position. If the closure is operating correctly (locked) when the test is employed the guard closure should neither be open nor should it open in response to the tester probe. 
     Referring specifically to the three figures which illustrates different positions of the same embodiment there is shown by way of example only a hinged closure  100  that is being tested. The invention is applicable to testing slidably or otherwise movable closures as well as fixed closures while in their hazard protective status. Similarly, the instant embodiment can use a pusher probe of any suitable force including a pulsating force. Likewise, testers other than a pusher type can utilize the testing method described here. 
     The tester assembly  102  in FIG. 9 is shown connected to a rigid mount  104  that is connected to a machine bed  106 . Also secured to the machine bed is a closure lock  108  that is designed to maintain the closure in the locked position. As aforementioned, the purpose of the subject test is to determine if the closure cannot be opened, or it can be opened due to whatever cause, one of which can be the failure of the lock. Furthermore, this tester assembly  102  is capable of being checked during testing to determine that the tester probe is functioning correctly. If a separate interlock which is an integral interlock-lock is to be tested the lock  108  can be designed to be unlatched and relatched as required by such a test. Because of this action the unlatching and latching functions of the integral lock are also tested for. The testing device of FIGS. 9,  10  and  11  can be utilized in conjunction with the flow diagrams discussing the operation of the various routines for testing guard closures, interlocks and locks etc., disclosed in detail with respect to FIGS. 2-6 previously described. 
     To test whether the closure  100  is closed and cannot be opened, or can be opened or is open the tester assembly includes a probe  110  located in a housing  112 . The probe  110  is moved by a tester/motor actuator  114  located at the rear of the housing  112 . The probe  110  has secured to its outer end thereof a gripper member  116  that includes a set of jaws that are in the normally open position. The gripper member  116  includes a touch trigger (not shown) which when it comes into contact with the closure handle  120  closes the gripper jaws around the closure handle  120 . This type of gripper, because of its touch trigger, will latch on to the closure handle regardless if the closure cannot be opened, or if it can be opened, or if it is open. The movement of the probe assembly  110  is limited by the collar  118  which will engage the housing when in its extended position as shown in FIG.  11 . 
     Attached to the collar  118  is a probe displacement contact member  122  that during probe movement glides along the probe position sensor  124  that is mounted in the probe housing  112 . The position sensor can be a continuous strip or can consist of a row of discrete position sensors and functions to indicate the position of the probe which is suitably recorded. As shown in FIG. 9 the gripper  116  is spaced from the handle  120  by a gap. When the test is initiated, the probe is commanded to move the probe gripper  116  toward the closure handle  120 . If the gap between them is closed, then this gap closure will be indicated by the contact member  122  on the position sensor  124 , and such movement will determine that the probe  110  has deployed. If no movement was indicated, then the probe  110  has failed to deploy for testing, which is a tester failure. When the probe  110  is moved by the tester motor  114  the position is monitored by the sliding movement of the contact member  122  relative to the position sensor  124 . 
     Turning to FIG. 10 there is shown the position of the various components when the gripper member of the tester probe comes into gripping contact with the handle  120  of the hinged closure. In that position it is assumed that the closure remains in the closed position and cannot be opened by the tester probe. Suitable indicators will record this movement to show that the probe  110  moved only that amount to engage the closure handle  120  and thus that the guard closure passed the test in that it remained in the closed position. In the event the closure can be opened or is open the closure is moved to the open position shown in FIG. 11 by the power driven probe  110 . When this occurs the sensors  124  will indicate that the probe has extended a certain distance and thus the closure did fail its test. When the test is completed the tester is retracted and tests are conducted to check if the tester returned to the position shown in FIG.  9 . The retraction action forces open the gripper jaws of the tester. 
     The above mentioned probe retraction may result in the probe retracting only partially or not at all. In that case, it will be so indicated by the position of the contact member  122  on the position sensor  124 , which will thereby signal that the probe  110  has failed to retract as commanded, which is a tester failure. 
     Turning now to FIGS. 12,  13 ,  14  and  15  there is illustrated an arrangement in which there is the testing of a closure guard by a force displacement member identical to that disclosed in FIGS. 9-11. The identical components are given the same numbers and the description of their operation is set forth in the previous paragraphs. This arrangement distinguishes from the previous design in that the closure tester assembly is connected to an interlock assembly that is resiliently mounted to the machine base. Also, this arrangement performs both the closure test and interlock test simultaneously, with the same common tester as is illustrated in FIGS. 12 through 15. The arrangement works equally well when the interlock is attached to the tester and the tester is resiliently mounted to the machine base. FIGS. 7A,  7 B,  7 C and  7 D previously described, discloses a flow chart as to how the various components are tested and what takes place in the event the closure and/or interlock passes or fails its tests. 
     Referring first to FIG. 12 it is noted that tester assembly  102  is secured to an interlock  132  which is in turn secured to a resilient base  134  that is connected to the machine base  106 . Lock  108  is also connected to the machine base and functions to lock the hinged closure  100  in position against the machine base. As shown, the interlock  132  has a sensor member  136  in contact with the hinged guard  100 . The testing of this type of interlock arrangement is described in detail with respect to FIGS. 6-7 of the aforementioned U.S. Pat. No. 5,870,317. The interlock normally acts to turn off the machine when the guard is opened or its state is otherwise changed. Therefore, during the testing the interlock is bypassed so that testing can proceed while the machine is running, without the test shutting down the machine. The previously described flow chart in FIGS. 7A,  7 B,  7 C and  7 D sets forth in detail the testing procedure of the closure and interlock. 
     Also in FIG. 12 there is shown a tester displacement rigid blocker  142  which is connected to the machine base  106 . This blocker has a sensor contact  144  attached to it and a matching sensor contact  146  is located on the near end of the test assembly  102 . 
     The combined closure and interlock testing of the embodiment shown in FIGS. 12,  13 ,  14  and  15  starts by the tester/motor actuator  114 , being commanded to move the probe  110  toward the closure  100 . As previously described with respect to FIG. 9, if by this probe movement the gap present between the gripper  116  and the closure handle  120  shown in FIG. 12 is closed, then the contact member  122  will indicate this on the position sensor  124 , and such movement will determine that the probe  110  has deployed. If no movement is indicated, then the probe did not deploy for testing, which is tester failure. 
     If the probe does deploy, then the gripper jaws  116  will engage the closure handle  120  and latch on to it, as shown in FIG.  13 . At this stage the tester/motor actuator  114  continues pushing the probe  110  toward the closure  100 . If the closure is closed and cannot be opened then the situation shown in FIG. 14 will take place. 
     As shown in FIG. 14 the tester  102  and interlock  132  will move in the direction away from the closure  100 , ending up butting against the rigid blocker  142 . This is made possible because the resilient base  134  will distort as shown in FIG. 14, to accommodate this movement. The contact sensors  144  and  146  will indicate that this butting of the tester  102  against the blocker  142  has taken place. This indication together with the position of the contact member  122  on the position sensor  124  will indicate that the closure  100  is not open and cannot be opened, and the closure has passed the test. 
     As is further shown in FIG. 14, the butting position of the tester  102  against the rigid blocker  142  removes the interlock from contact with the closure  100 , and thus frees the interlock sensor member  136  to be able to change to its “guard open” position. This tests the interlock as described in detail with respect to FIGS. 6 and 7 of the aforementioned U.S. Pat. No. 5,870,317. 
     At the completion of the combined closure and interlock test of FIG. 14, the tester/motor actuator  114  is commanded to retract the probe  110  to the position shown in FIG.  12 . The retraction action forces open the gripper jaws of the probe, freeing the closure from the probe. 
     As is shown in FIG. 12, the retracted position returns the interlock sensor member  136  to its “guard closed” position. Checking if this return results in the change of the interlock to its “guard closed” state constitutes the second part of the interlock testing routine as described in detail with respect to FIGS. 6 and 7 of the aforementioned U.S. Pat. No. 5,870,317. 
     The previously mentioned command to retract the probe  110  from the position shown in FIG. 14, to that shown in FIG. 12, may result in the probe retracting only partially or not at all. In that case, it will be so indicated by the position of the contact member  122  on the position sensor  124 , which will thereby signal that the probe  110  has failed to retract as commanded, which is a tester failure. 
     If the tester shows that the closure  100  can be opened or is open, then this constitutes a closure failure. The situation shown in FIG. 15 typifies this, if the opening resistance of the closure  100  to the force applied to it by the probe  110  is sufficiently large. As shown, the tester  102  and the interlock  132  will move in the direction away from the closure  100 , ending up butting against the rigid blocker  142 . This is made possible because the resilient base  134  will distort as shown in FIG. 15, to accommodate this movement. The contact sensors  144  and  146  will indicate that this butting of the tester  102  against the blockers  142  has taken place. This indication, together with the extended position of the contact member  122  on the position sensor  124  will indicate that the closure  100  can be opened or is open hence has failed the test. 
     The situation can ensue, such that the closure  100  opens so easily or so far that the resilient mount  134  does not distort or does not distort sufficiently to cause a butting contact between the tester  102  and the rigid blocking member  142 . In this situation the probe ends up in its fully extended position. The position of the contact member  122  on the position sensor  124  will indicate that this is the case, and thereby indicate that the closure can be opened or is open, and thus the closure has failed the test. 
     In either closure open or opening case described above, the interlock sensor member  136  is removed from contact with the closure  100 , and thus frees the interlock sensor member  136  to be able to change to its “guard open” position. This tests the interlock as described in detail with respect to FIGS. 6 and 7 of the aforementioned U.S. Pat. No. 5,870,317. 
     At the completion of the closure test for which the indication is that the closure  100  can be opened or is open, the tester/motor actuator  114  is commanded to retract the probe  110  to the position shown is FIG.  12 . The retraction action forces open the gripper jaws of the probe, freeing the closure from the probe. 
     The retracted position returns the interlock sensor member  136  to its “guard closed” position. Checking if this return resulted in the change of the interlock to its “guard closed” state constitutes the second part of the interlock testing routine as described in detail with respect to FIGS. 6 and 7 of the aforementioned U.S. Pat. No. 5,870,317. 
     The previously mentioned command to retract the probe  110  to the position shown in FIG. 12, may result in the probe retracting only partially or not at all. In that case it will be so indicated by the position of the contact member  122  or the position sensor  124 , which will thereby signal that the probe  110  has failed to retract as commanded, which is a tester failure. 
     It is intended to cover by the following claims all embodiments which fall within the true spirit and scope of the invention.