Patent Application
20140148940
This invention relates to a machine tool and more particularly to as system responsive to a malfunctioning condition in the operation of such machine for deactivating the machine.
CNC routing machines are used in manufacturing processes for routing, drilling, trimming and other operations in forming various workpieces. The automatic nature of such machines allows the machine operator to engage in ancillary tasks during a machining cycle, therefore making efficient use of otherwise idle time. From time to time, in the operation of such machines, any number of uncontrollable events such as tool breakage, dislocation of workpieces and the like could occur while the machine is in an automatic operating mode. Should such a malfunction occur, it would be beyond the capability of the machine control to detect the fault and stop the machine for the purpose of undertaking remedial action. Typically, under such circumstances, the operator must go immediately to the machine, activate a pause or stop function in order to make the required adjustments, observations and/or other corrective procedures.
Manufacturers provide systems such as pressure activated mats, photo-electric beam systems or any number of other sensing devices for the purpose of stopping the machine and providing for safe entry into the machine operating zone. Such systems, however, are costly, often cumbersome in nature and are vulnerable to damage from activities such as loading and/or unloading the machine. Furthermore, because such systems require point-of-contact activation, the amount of time required to gain access to the machine from a remote location could result in damage to a workpiece and/or the machine. More importantly, excessive delay and stopping the machine could result in injury to the operator and/or other personnel in the vicinity of the machine.
Accordingly, the principal object of the present invention is to provide a system permitting a machine operator disposed at a distance from a malfunctioning machine to deactivate the machine from such distance.
The principal object of the present invention is achieved by providing a system for remotely deactivating the operation of a machine tool responsive to an adverse condition in the operation of the machine, including an electrical circuit including an electrically actuated relay interconnecting a voltage source and an input port of a control unit of the machine, functional upon closure of such relay to pause the operation of the machine; a receiver responsive to an R-F signal operative to electrically actuate such relay; and means displaceable relative to the electrically actuable means for selectively transmitting an R-F signal to such receiver. Such an adverse condition may consist of a malfunction of a tool, a displacement of a tool or a malfunction of means for retaining a workpiece on the machine. Such relay may be provided in a control unit of the machine apart from a signal receiver provided in a separate module or provided in a separate module with the signal receiver. Preferably, the transmitter consists of a portable, handheld receiver, the range of the receiver is 100 feet, the transmitted signal is coded and the remote receiver includes an encoder.
Referring to
Module 13 includes a first circuit 28 disposed parallel to the other input circuits of the control panel, interconnecting a voltage source and an input port of input/output interface 16 and includes a relay switch 29, and a second circuit 30 provided with a voltage source, a receiver 12 with an antenna 31 and including a latching logic component 31 and the actuating coil of switch 29. Alternatively, relay switch 29 can be disposed in control panel 15 and may consist of any type of electrically actuating switch including solid state switches. Upon closure of switch 29, computer 17 functions to deactivate the entire machine to permit remedial action with respect to any component malfunction. Upon remedying the malfunction, the operation of the machine may be resumed by triggering reset switch 27. The components of module 13 may be integrated into the control unit of the machine, provided in a separate module mounted on the control unit or placed in a module positioned adjacent the control unit.
Transmitter 14 is a device operatively compatible with receiver 12 to selectively generate a coded R-F signal to activate receiver 12. It is portable so that it can be carried by the machine operator and has a range of 100 feet. Receiver 12 is functional to receive and decode R-F signals generated by transmitter 14, energizing circuit 30, correspondingly closing switch 29 to effect a pause in the operation of a the machine.
In the typical use of a CNC machine equipped with the deactivating system, an operator would load the workpieces to be machined on the worktable of the machine, utilizing various holddown devices including clamps and vacuum devices, input a selected machine program into the control unit of the machine and then actuate a cycle start switch in the control unit to execute the loaded program. Under such operating conditions, the workpieces would be retained in their selected positions, the servo motors would be displaced along the x, y and z axes pursuant to the program being executed, and the motor spindle would be operated to machine the loaded workpieces. With the machine thus operating, the operator would be free to perhaps set up and operate one or more similar machines in the near vicinity, attend to gathering, sorting and transporting machined workpieces to other departments, possibly assembling machine components and otherwise which may cause the operator to depart from the vicinity of the machine under operation.
Upon being distanced from the machine and being alerted to a malfunction of the machine such as a displacement of a workpiece, a broken tool or any other such malfunction, the operator would be able to deactivate the machine simply by triggering his portable transmitter causing switch 29 to close and correspondingly deactivate the machine into a pause condition. Upon return to the vicinity of the machine, determining and remedying the malfunction of the machine, the operator would resume the routine operation of the machine by actuating reset switch 27.
The circuit including pause switch 29 may be integrated in control panel 15 or may be disposed in a module mounted on the control panel or disposed apart from the machine. Depending on the location of pause switch 29, receiver 12 can be integrated into the control panel or provided in a module mounted on the machine or disposed apart from the machine.
From the foregoing detailed description, it will be evident that there are a number of changes, adaptations and modifications of the present invention, which come within the province of those persons having ordinary skill in the art to which the aforementioned invention pertains. However, it is intended that all such variations not departing from the spirit of the invention be considered as within the scope thereof as limited solely by the appended claims.
