Abstract:
A vibration welding system and method having an operating vibration frequency of 260 Hz or higher. A pressing action between two workpieces is effected by directly controlling, with a control system and a sensor, the relative positions of the workpieces during some or all of the weld cycle, or by controlling the speed between the workpieces during some phase of the weld cycle and controlling the force between the workpieces during other phases. An external control device can be coupled to a control system, to produce an input signal to adjust the speed of relative motion between the workpieces, the force therebetween, or both speed and force based on the input signal. A positive force can be initially applied between the workpieces, and the weld is started by initiating lateral vibrations while the relative position between the workpieces in the pressing direction is maintained, a control variable is monitored, and the second workpiece is moved relative to the first only after the monitored variable satisfies a condition.
Abstract:
An ultrasonic welding system includes a motion control system that is coupled to and that causes controlled movement of an ultrasonic welding stack, in accordance with control inputs that are based on one or more control signals that are received from one or more sensors. The motion control system initiates a welding operation, subsequent to which an initial motion delay occurs until a predetermined condition is satisfied. Subsequently, in response to the predetermined condition being satisfied, the ultrasonic welding stack is caused to move in accordance with a weld profile. Subsequently, in response to an occurrence of a predetermined delay initiating condition, the ultrasonic welding stack is caused to stop motion and to maintain a stationary position. Subsequently, in response to an occurrence of a predetermined delay terminating condition, motion of the ultrasonic welding stack is resumed in accordance with the weld profile.
Abstract:
An ultrasonic welding system includes a motion control system that is coupled to and that causes controlled movement of an ultrasonic welding stack, in accordance with control inputs that are based on one or more control signals that are received from one or more sensors. The motion control system initiates a welding operation, subsequent to which an initial motion delay occurs until a predetermined condition is satisfied. Subsequently, in response to the predetermined condition being satisfied, the ultrasonic welding stack is caused to move in accordance with a weld profile. Subsequently, in response to an occurrence of a predetermined delay initiating condition, the ultrasonic welding stack is caused to stop motion and to maintain a stationary position. Subsequently, in response to an occurrence of a predetermined delay terminating condition, motion of the ultrasonic welding stack is resumed in accordance with the weld profile.
Abstract:
An ultrasonic welding system includes a motion control system that is coupled to and that causes controlled movement of an ultrasonic welding stack, in accordance with control inputs that are based on one or more control signals that are received from one or more sensors. The motion control system initiates a welding operation, subsequent to which an initial motion delay occurs until a predetermined condition is satisfied. Subsequently, in response to the predetermined condition being satisfied, the ultrasonic welding stack is caused to move in accordance with a weld profile. Subsequently, in response to an occurrence of a predetermined delay initiating condition, the ultrasonic welding stack is caused to stop motion and to maintain a stationary position. Subsequently, in response to an occurrence of a predetermined delay terminating condition, motion of the ultrasonic welding stack is resumed in accordance with the weld profile.
Abstract:
An ultrasonic welding system includes an ultrasonic welding stack that is movable to initiated a welding operation. A plurality of sensors measure respective control variables and output control signals corresponding, respectively, to the control variables. A motion control system is coupled to and causes controlled movement of the welding stack, including initiating the welding operation. The motion control system determines, based on the control signals, control inputs such that any motion of the welding stack, subsequent to the initiating, is initially delayed until the control signals satisfy a predetermined condition. In response to the predetermined condition being satisfied, the motion control system causes the welding stack to move in accordance with a weld profile.
Abstract:
An ultrasonic welding system and method for joining first and second thermoplastic parts includes least one energy director formed on at least one surface of the first thermoplastic part, with the energy director projecting from the surface of the first thermoplastic part toward an opposed surface of the second thermoplastic part. The distal end portion of the energy director has a curved or flat surface that initially engages the opposed surface of the second thermoplastic part when the first and second parts are brought into engagement with each other. The first and second thermoplastic parts are ultrasonically welded by pressing the parts together while vibrating at least the first part in a direction parallel to the direction of projection of the energy director. The energy director may include a pair of substantially flat side walls joined to opposite ends of the curved or flat end surface.
Abstract:
An ultrasonic welding system includes a movable ultrasonic welding stack, an electrically powered linear actuator with a servo motor and a movable element, a controller, and at least two sensors. The controller causes the ultrasonic welding stack to apply a predetermined positive initial force to at least one workpiece prior to initiation of welding. The controller further causes the ultrasonic welding stack to initiate subsequent movement of the ultrasonic welding stack, following initiation of welding, only after the signal outputs from the at least two sensors indicate that a combination of control variables satisfies a predetermined condition.
Abstract:
An ultrasonic welding system includes a movable ultrasonic welding stack, an electrically powered linear actuator with a servo motor and a movable element, a controller, and at least two sensors. The controller causes the ultrasonic welding stack to apply a predetermined positive initial force to at least one workpiece prior to initiation of welding. The controller further causes the ultrasonic welding stack to initiate subsequent movement of the ultrasonic welding stack, following initiation of welding, only after the signal outputs from the at least two sensors indicate that a combination of control variables satisfies a predetermined condition.
Abstract:
An ultrasonic welding system includes an ultrasonic welding stack that is movable to initiated a welding operation. A plurality of sensors measure respective control variables and output control signals corresponding, respectively, to the control variables. A motion control system is coupled to and causes controlled movement of the welding stack, including initiating the welding operation. The motion control system determines, based on the control signals, control inputs such that any motion of the welding stack, subsequent to the initiating, is initially delayed until the control signals satisfy a predetermined condition. In response to the predetermined condition being satisfied, the motion control system causes the welding stack to move in accordance with a weld profile.
Abstract:
An ultrasonic welding system and method for joining first and second thermoplastic parts includes least one energy director formed on at least one surface of the first thermoplastic part, with the energy director projecting from the surface of the first thermoplastic part toward an opposed surface of the second thermoplastic part. The distal end portion of the energy director has a curved or flat surface that initially engages the opposed surface of the second thermoplastic part when the first and second parts are brought into engagement with each other. The first and second thermoplastic parts are ultrasonically welded by pressing the parts together while vibrating at least the first part in a direction parallel to the direction of projection of the energy director. The energy director may include a pair of substantially flat side walls joined to opposite ends of the curved or flat end surface.