Patent Application
20110248008
1. Field
Embodiments of the present invention relate to methods and apparatuses for controlling welding systems. More particularly, various embodiments of the invention provide methods and apparatuses for wirelessly controlling welding systems with remote foot pedals.
2. Description of Related Art
Welding systems, such as tungsten inert gas (TIG), metal inert gas (MIG), and shielded metal arc (SMAW) welding systems, may be controlled by foot pedals to enable operators to vary welding parameters. Typically, foot pedals are difficult to interface with welding systems or are connected to welding systems by cables—thereby inhibiting operator movement and pedal use.
Accordingly, there is a need for an improved controller for welding systems that does not suffer from the problems and limitations of conventional systems.
The present teachings provide an improved apparatus for controlling welding systems that does not suffer from the limitations of the prior art. Particularly, embodiments of the present technology provide a method and apparatus for wirelessly controlling welding systems with remote foot pedals.
According to a first embodiment of the invention, a wireless controller comprises a housing including a first portion and a second portion moveably attached to the first portion. The first portion supports the controller relative to an external surface and is adjustable between an elevated position and a collapsed position, wherein a first end of the first portion is elevated relative to a second end of the first portion when the first portion is in the elevated position. A sensing element senses a position of the second portion relative to the first portion and provides a corresponding position signal. A transmitter is coupled with the sensing element and wirelessly transmits the position signal.
According to a second embodiment of the invention, a wireless controller comprises a housing with a base portion and a pivoting portion pivotable relative to the base portion, a rotary potentiometer for providing a position signal, and a pinion coupled with the rotary potentiometer. A rack is in intermeshing engagement with the pinion and in sliding engagement with the pivoting portion of the housing, and a spring element biases the rack against the pivoting portion of the housing. A transmitter is coupled with the potentiometer for wirelessly transmitting the position signal.
This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
Preferred implementations of the present technology are described in detail below with reference to the attached drawing figures, wherein:
The following detailed description of various embodiments of the invention references the accompanying drawings which illustrate specific embodiments in which the invention can be practiced. The embodiments are intended to describe aspects of the invention in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments can be utilized and changes can be made without departing from the scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense. The scope of the present invention is defined only by the appended claims, along with the full scope of equivalents to which such claims are entitled.
Referring initially to
The welding system 12 may be any welding system including the electrical control interface 18 to enable the reception of an electrical signal for control of one or more functions of the welding system 12. For example, the welding system 12 may be a tungsten inert gas (TIG), metal inert gas (MIG), and/or shielded metal arc (SMAW) welding system. In some embodiments, the welding system 12 is a TIG system and the electrical control interface 18 is an amperage control interface operable to receive a control signal to vary the output current of the welding system 12. For example, the welding system 12 may be a Syncrowave(R) 350 LX TIG/STICK welding system manufactured by Miller Electric Mfg Co. including the electrical control interface 18 to couple with a cable associated with a control device such as a wired foot pedal. Thus, the control system 10 may be adapted to replace a wired foot pedal associated with the welding system 12. However, the control system 10 may be adapted to control any function of any welding system having an electrical control interface.
Referring to
As best illustrated in
Other housing configurations may be employed without departing from the scope of the present teachings. By way of example, principles of the present teachings may be incorporated into virtually any housing configuration involving a first portion and a second portion moveable relative to the first portion.
In some embodiments, the base portion 20a includes an elevator element 26 operable to raise a portion of the housing 20 to facilitate pivoting of the pivoting portion 20b. For example, the elevator element 26 may include a U-shaped bracket that is operable to pivot between a stowed position and a deployed position. In the deployed position, the elevator element 26 engages an external surface, such as a floor, and supports a first end of the housing 20 in an elevated position relative to a second end of the housing 20 (see
The elevator element 26 may be adjustable between the stowed position and a plurality of deployed positions, wherein each deployed position corresponds to a unique elevated position of the foot pedal 14. By way of example, multi-position adjustability may be accomplished using an adjustable A-frame configuration, a ratcheting mechanism, a plurality of detents, and so forth.
It will be appreciated that the elevator element 26 is generally operable to adjust the foot pedal 14 between one or more elevated positions and the collapsed position, and is not limited to a particular shape or size disclosed herein. By way of example, the elevator element 26 may include one or more telescoping members operable to be selectively extended to any of various positions corresponding to different heights of the foot pedal 14.
If a user is operating the welding system 12 while lying on his or her back under a vehicle, it may be difficult and/or uncomfortable to operate the foot pedal 14 if the foot pedal 14 is lying flat on the ground (in the collapsed position,
The pivoting portion 20b is pivotably coupled with the base portion 20a and is operable to be at least partially pivoted by the operator. For example, the operator may press on a portion of the pivoting portion 20b to pivot the pivoting portion 20b in relation to the base portion 20a. In some embodiments, the base portion 20a may present a generally oval shape or a generally rectangular configuration with rounded ends and/or corners, and the pivoting portion 20b may be at least partially beveled to enable the pivoting portion 20b to easily pivot in relation to the base portion 20a. However, the pivotable housing 20 may present any configuration that is operable to be at least partially pivoted or otherwise depressed by the operator, including conventional configurations.
The pivotable housing 20 may be formed from various materials, including metals, plastics, combinations thereof, and the like. In some embodiments, the pivotable housing 20 may be comprised of aluminum, steel, or other similar materials to provide rigidity and stability. Alternatively, the pivotable housing 20 may be comprised of poly carbonate or other fiber materials to minimize interference with signals generated by the transmitter 24. Utilization of poly carbonate and other similar materials may reduce or eliminate the need for antennas external to the housing 20. In an exemplary implementation, the housing 20 is formed of a long fiber plastic material with a certain glass content for added durability without sacrificing signal transmission allowance. The amount of glass in the material may be within the range of about 10% to about 50% or within the range of about 20% to about 40%. More particularly, the amount of glass in the material may be about 25%, about 30%, or about 35%. By way of example, the housing 20 may be formed of LNP VERTON RF 700-10 EM HS or similar materials.
The sensing element 22 is coupled with the pivotable housing 20 and is operable to sense a position of the pivotable housing 20 and provide the corresponding pedal position signal. Thus, for example, the sensing element 22 may sense the extent to which the pivotable housing 20 has been pivoted by the operator, such as the amount the pivoting portion 20b has been pivoted in relation to the stationary base portion 20a, and provide the corresponding pedal position signal.
In some embodiments, the sensing element 22 may include a rotary potentiometer 27. The potentiometer 27 may be coupled with the pivotable housing 20 to rotate as the pivotable housing 20 pivots. As the potentiometer 27 rotates, the resistance it provides to a supplied current changes to produce the pedal position signal for transmission by the transmitter 24. The potentiometer 27 may be coupled with the pivotable housing 20 in any manner to rotate or otherwise actuate as the housing 20 is pivoted. For example, and as explained below in greater detail, the potentiometer 27 may be actuated via a rack and pinion assembly upon movement of the pivoting portion 20b.
In some embodiments, the potentiometer 27 may present a non-rotary configuration and additionally or alternatively include linear, spindle operated, panel mount, switched, multi-turn, multi-gang, sealed or unsealed potentiometers. Further, in some embodiments, the sensing element 22 may provide potentiometer-like functionality to detect the position of the pivotable housing 20 without including a potentiometer.
The sensing element 22 may additionally or alternatively include rotary encoders, piezoelectric sensors, Hall-effect sensors, inductive sensors, linear voltage detection transmitters, pressure transducers, infrared sensors, optical sensors, magnetic sensors, switches, rheostats, combinations thereof, and the like, to sense the position of the pivotable housing 20 and/or the extent to which the housing 20 is pivoted. Thus, the sensing element 22 may include any element or combination of elements operable to sense the position of the pivotable housing 20 and provide the corresponding pedal position signal. The pedal position signal provided by the sensing element 22 may be any analog and/or digital signal.
As illustrated in
The foot pedal 14 may include an integral power source 30 to power the transmitter 24 and/or other components to enable the foot pedal 14 to operate without any external wires. The power source 30 may comprise one or more batteries, a battery pack, a receptacle for receiving one or more batteries or a battery pack, a solar cell, combinations thereof, and the like. In some embodiments, the power source 30 may be rechargeable and be associated with a charging port to receive electrical power for recharging from an external device or system, such an electrical outlet.
The transmitter 24 is coupled with the sensing element 22 and operable to wirelessly transmit the pedal position signal provided by the sensing element 22 for reception by the receiver 16. The transmitter 24 may include any element or combination of elements operable to wirelessly transmit the pedal position signal, including processors and antennas, for reception by the receiver 16. For example, the transmitter 24 can include radio and/or infrared transmitting elements. The transmitter 24 may additionally include other elements to facilitate coupling with the sensing element 22. For example, the transmitter 24 may include or be coupled with an analog-to-digital converter, digital-to-analog converter, and other signal processing elements. In some embodiments, portions of the transmitter 24, such as the antenna, may be positioned outside of the pivotable housing 20 to facilitate signal transmission. However, in other embodiments, the transmitter 24 may be entirely enclosed by the pivotable housing 20.
In some embodiments, the transmitter 24 may include a digital radio transmitter, such as a ZigBee-compliant (IEEE 802.15.4) transmitter operable to encode the pedal position signal into a plurality of digital packets. For example, the transmitter 24 may include an XBee radio module manufactured by MaxStream, Inc. of Lindon, Utah. However, other methods may be utilized by the transmitter 24 to transmit signals, including Bluetooth, WiFi, ultra wide-band, Wi-Max, frequency and/or amplitude modulation, combinations thereof, and the like. The transmitter 24 may be adapted to transmit digital signals, analog signals, and/or a combination of digital and analog signals. In some embodiments, the effective communication range between the transmitter 24 and receiver 16 may controlled by varying the output power of the transmitter 24.
In embodiments including the limit switch 28, the transmitter 24 may be coupled with both the sensing element 22 and limit switch 28. In such embodiments, the transmitter 24 is operable to transmit the pedal position signal in a manner that corresponds to the signals provided by the sensing element 22 and transmitter 24. For example, the potentiometer 27 can provide a potentiometer position signal, the limit switch 28 can provide a limit switch position signal, and the transmitter 24 can transmit the pedal position signal in a manner that reflects both the potentiometer and limit switch signals.
Further, the transmitter 24 may also be coupled with the power source 30 and transmit the pedal position signal with an indication of the status of the power source 30, such as battery level. Thus, the pedal position signal transmitted by the transmitter 24 may indicate the position of the potentiometer 27, the status of the limit switch 28, and the status of the power source 30. However, the pedal position signal may only indicate the position of the pivotable housing 20 as sensed by the sensing element 22 in some embodiments.
The pedal position signal may also identify and/or authenticate the operator. For example, the operator may fully depress the pivotable housing 20 three times, or in any other unique sequence, to cause the transmitter 24 to transmit the pedal position signal with an identification and/or authentication of the operator. Such identification can be used by the transmitter 24, receiver 16, and welding system 12 to automatically provide configuration settings previously set by the operator in the event the control system 10 and welding system 12 are used by more than one operator. The foot pedal may also include one or more interface elements 32, such as connectors, buttons, switches, and the like. The interface element 32 may include an electrical communications connector, a power connector for energizing the pedal 14 and/or charging the power source 30. Furthermore, the interface element 32 may include a button or switch for turning the foot pedal 14 off and on, and/or for identification and authentication purposes.
In embodiments where the pedal position signal indicates more than the position of the pivotable housing 20, use of digital radio methods to transmit the signal may be desirable to limit the amount of communication required between the foot pedal 14 and receiver 16. For example, a single digital radio packet may indicate: one or more positions of the pivotable housing 20 as sensed by potentiometer 27; the status of the limit switch 28; the status of the power source 30; the identity of the operator; and/or various communication information such as the identity of the transmitter 24 and the channel being utilized by the control system 10.
In some embodiments, the transmitter 24 may be reprogrammed by the operator to modify the manner in which the pedal position signal is transmitted. For example, the foot pedal 14 may include a transmitter programming interface 34, such as a USB, RS-232, or other wired or wireless data interface, associated with the transmitter 24 to enable the operator to reprogram and/or otherwise communicate with the transmitter 24. The transmitter programming interface 34 may further include one or more buttons, knobs, or switches, such as a rotary encoder or a series of DIP switches, for frequency adjustment or otherwise enabling a user to directly control one or more functions of the transmitter 24. For instance, the transmitter 24 may be programmed to process, adjust, or otherwise modify the pedal position signal before transmission to the receiver 16, such as by modifying the minimum and maximum values to be provided to the welding system 12. The transmitter programming interface 34 may be accessible via a first access port 36.
In some embodiments the potentiometer 27 may provide a linear (direct) relationship between its output and the position of the pivotable housing 20—such as by providing a 0% output when the pivotable housing 20 has not moved and a 100% output when the pivotable housing 20 is fully depressed. Such a linear relationship may not be desirable in all environments and the transmitter 24 may be programmed to scale the signal provided to the potentiometer 27 to more desirable levels—such as by correlating the maximum position indicated by the pedal position signal to where the pivotable housing 20 is depressed only 80% as sensed by the potentiometer 27. The receiver 16 may additionally or alternatively perform this functionality.
The transmitter 24 may also be programmed with a unique identifier, channel information, network information, and/or other communication information to enable the transmitter 24 and receiver 16 to communicate with limited interference from other devices. For example, in some embodiments, the foot pedal 14 may be one of several remote devices associated with the welding system 12 and the communication information enables the transmitter 24 and receiver 16 to communicate without significantly interfering with the other remote devices. Further, the foot pedal 14 may be associated with several welding systems 12 to separately or simultaneously control their functionality.
In some embodiments, the foot pedal 14 may be configured for a sleep mode to extend the life of the power source 30. For example, if the sensing element 22 and/or limit switch 28 detect that the pivotable housing 20 has not been depressed for a certain time period, the foot pedal 14 may enter a sleep mode to only periodically utilize the sensing element 22. The configuration of the sleep mode may be varied by utilizing the transmitter programming interface 34, such as by defining when and if the sleep mode should be utilized and the various sleep and wake time periods utilized by the sleep mode.
Referring to
The antenna 38 may be any element or combination of elements operable to receive signals transmitted by the transmitter 24. In embodiments where the transmitter 24 transmits radio frequency signals, the antenna 38 may include a radio frequency antenna and associated circuitry. For example, the antenna 38 may be matched with the transmitter 24 to ensure the proper reception of signals. In embodiments where the transmitter 24 transmits infrared signals, the antenna 38 may be an infrared detector (photodetector). Thus, the antenna 38 is not necessarily limited to receiving radio frequency signals using one or more conductive elements. The antenna 38 may be internal to the receiver housing and/or be an external antenna operable to couple with the receiver 16.
In some embodiments, the receiver 16 may include a relay 44 coupled with the processor 40 and connector 42. The relay 44 is operable to switch when controlled by the processor 40 to mimic the functionality of the limit switch 28, as is discussed in more detail below. The relay 44 may include any controllable switches operable to be controlled by the processor 40, including latching relays, reed relays, polarized relays, machine tool relays, solid state relays, combinations thereof, and the like.
The processor 40 is coupled with the antenna 38 and operable to process signals for use by the welding system 12, such as by converting the signal into an appropriate format for reception by the electrical control interface 18 and use by the welding system 12. For example, the pedal position signal may be an encoded digital radio signal and the processor 40 may decode the digital radio signal to generate an analog ratio metric signal for use by the welding system 12.
The processed pedal position signal provided to the welding system 12 may be a digital and/or an analog signal. For example, the processor 40 may include various switching elements and/or logic to present the processed pedal position signal as a variable voltage signal, a variable current signal, a variable resistance signal, a pulse-width modulated (PWM) signal, an unencoded digital signal, an encoded digital signal, combinations thereof, and the like.
The processor 40 may also scale the pedal position signal into a voltage or current range acceptable for use by the welding system 12. For example, the welding system 12 may require a 0-10V signal to be provided through the electrical control interface 18 to control welding current. If the amplitude to the pedal position signal received by the receiver 16 is not within this range, the processor 40 may scale (e.g., amplify) the pedal position to the appropriate range. Such a configuration enables the receiver 16 to be adapted to universally couple with any welding system 12 and electrical control interface 18 to provide appropriate control signals thereto.
The processor 40 may also process the pedal position signal to function the relay 44. For example, as discussed above, the pedal position signal may include an indication of the status of the limit switch 28. In such embodiments, the processor 40 may identify the status of the limit switch 28 based on the pedal position signal and function the relay 44 to correspond to the position of the limit switch 28. Such a configuration enables the control system 10 to be used with welding systems that require both a variable pedal position input and a limit switch input (ground common or positive common).
For example, when the pivotable housing 20 is at least partially pivoted, the limit switch 28 may close to provide the limit switch position signal, which may be represented by the transmitted pedal position signal. The processor 40 may process the pedal position signal to determine that the limit switch 28 is closed and provide an appropriate signal to the relay 44 to close the relay 44. Thus, the relay 44 may mimic the functionality provided by limit switches included within conventional cabled control devices. Signals provided by the relay 44 may be represented by the processed pedal position signal provided to the welding system 12 through the connector 42.
The transmitter 24 may transmit signals for reception by the receiver 16 at any interval. In some embodiments where digital radio methods are employed, a packet corresponding to the pedal position signal is transmitted about every 50 ms. However, the control system 10 may be operable to vary this transmission rate to increase or decrease system latency. For example, system latency may be reduced by increasing the rate at which the packets are transmitted. Alternatively, to reduce power consumption by the foot pedal 14 and receiver 16, the rate at which the packets are transmitted may be reduced.
The processor 40 may also provide other signal processing functions. For example, the processor 40 may process the pedal position signal to ensure that the pedal position signal is authentic and not an interfering signal transmitted by a device other than the foot pedal 14. For example, the processor 40 may be provided with a unique identifier, channel information, network information, and/or other communication information to correspond to the communication information provided to the transmitter 24. In some embodiments, the processor 40 may be reprogrammable to enable the operator to provide selected communication and control information to the processor 40.
For example, the receiver 16 may include a receiver programming interface 46, such as a USB, RS-232, or other wired or wireless data interface, associated with the processor 40 to enable the operator to rep ro gram and/or otherwise communicate with the processor 40. For example, the processor 40 may be programmed to process the pedal position signal in any desired manner before the signal is provided to the welding system 12 through the connector 42. The processor 40 may also programmed with the communication information discussed above. For example, in some embodiments, the foot pedal 14 may be one of several remote devices associated with the welding system 12 and the communication information enables the transmitter 24 and receiver 16 to communicate without significantly interfering with the other remote devices. The receiver 16 may also be configured to receive control signals from remote devices other than the foot pedal 14.
The processor 40 may include any elements or combination of elements operable to perform the various functions discussed herein. For example, the processor 40 may include a computing device, a microprocessor, a microcontroller, a programmable logic device, a digital signal processor, analog or digital logic, combinations thereof, and the like. In some embodiments, the processor 40 may include or be coupled with an analog-to-digital converter, digital-to-analog converter, and other signal processing elements.
The connector 42 is coupled with the processor 40 and operable to connect with the electrical control interface 18 associated with the welding system 12 to provide the processed pedal position signal thereto. In embodiments where the electrical control interface 18 provides an interface for a wired foot pedal, the connector 42 may mimic the configuration of the connector utilized by the wired foot pedal to enable the control system 10 to easily replace the wired foot pedal. Thus, in some embodiments, the connector 42 may present a standard electrical interface for connecting with the electrical control interface 18 of the welding system 12.
In some embodiments, the connector 42 may present a universal interface to connect with electrical control interfaces associated with a plurality of welding systems to enable the control system 10 to function in a variety of environments. However, as the welding systems may each present different electrical interface configurations, the connector 42 may be adaptable by the operator to conform to a desired electrical interface configuration. For example, the connector 42 may include a connector base 42a connected with the processor 40 and a plurality of interface harnesses 42b corresponding to a plurality of electrical interfaces utilized by different welding systems. Each interface harness 42b is operable to interchangeably mate with the connector base 42a to enable the receiver 16 to couple with varying electrical interfaces. However, in some embodiments, the connector 42 may present a fixed electrical interface or be replaceable with other connectors to facilitate coupling with the welding system 12.
The connector 42 may also enable the receiver 16 and its various components to be powered by the welding system 12 by receiving an electrical signal from the welding system 12. In some embodiments, the receiver 16 may include power conditioning circuitry to enable it to be powered by welding systems that present varying voltages and currents. Utilization of the connector 42 to receive power enables the receiver 16 to be compactly configured without requiring an internal power source such as a battery or battery pack. However, in some embodiments, the receiver 16 may include an internal power source to function independent of any power provided by the welding system 12 through the connector 42.
Further, the receiver 16 may receive other signals from the welding system 12 through the connector 42. For example, the receiver 16 may be adapted to receive control, configuration, and/or command signals from the welding system 12 to dictate how the pedal position signal is to be received by the receiver 16 and/or processed and provided to the welding system 12. Thus, for instance, the receiver 16 may receive communication information from the welding system 12 to facilitate its communication with the foot pedal 14.
In some embodiments, the receiver 16 may include one or more indicators 48 coupled with the processor 40 and operable to indicate the status the receiver 16. For example, the indicators 48 may be operable to indicate the status of the pedal position signal such as by illuminating while the receiver 16 is receiving the pedal position signal from the foot pedal 14. The indicators 48 may also indicate the status of the connection with the welding system 12, such as by illuminating when the connector 42 is properly connected to the electrical control interface 18. In some embodiments, the processor 40 may identify the status of the power source 30 of the foot pedal 14 utilizing the pedal position signal and the indicators 48 may indicate the power source status to inform and alert the operator. The indicators 48 may include various indicating elements such as LEDs, seven segment displays, LCD monitors, speakers, combinations thereof, and the like.
The control system 10 may be configured to reduce the lag time between operation of the foot pedal 14 and the output provided by the welding system 12. For example, the transmitter 24 may be configured to transmit the pedal position signal with a stop command after the foot pedal 14 is returned to its rest position to enable the receiver 16 to identify that the foot pedal 14 is at rest and immediately provide the appropriate signal to the welding system 12 to halt operation. Alternatively, to increase lag time, the transmitter 24 may stop transmitting as soon as the foot pedal 14 returns to the rest position such that the receiver 16 holds the pedal position associated with the last received pedal position signal for a short time until it is determined that the transmitter 24 has stopped transmitting.
In operation, the operator may connect the receiver 16 to the welding system 12. For example, the operator may connect the connector 42 with the electrical control interface 18 of the welding system 12. In some embodiments, the operator may select one of the harnesses 42b for coupling with the connector base 42a to enable the connector 42 to properly mate with the electrical control interface 18. The operator may position the foot pedal 14 in any desirable location and function the foot pedal 14 by pivoting the pivotable housing 20. The sensing element 22 senses the position of the pivotable housing 20 and the transmitter 24 transmits the pedal position signal to the receiver 16. The processor 40 processes the received pedal position signal, such as by decoding and/or scaling the signal, and the processed signal is provided to the welding system 12 using the connector 42. The welding system 12 utilizes the received signal to control its operation, such as by varying its welding current in response to the pedal position. Thus, the operator may continuously control the operation of the welding system 12 by changing the position of the pivotable housing 20.
It is believed that embodiments of the present invention and many of its attendant advantages will be understood by the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely an explanatory embodiment thereof, it is the intention of the following claims to encompass and include such changes.
The rack 52 and pinion 50 may be formed from various materials, including metals, plastics, combinations thereof, and the like. In some embodiments, the rack 52 and pinion 50 may be comprised of aluminum, steel, or other similar materials to provide rigidity and stability. In an exemplary implementation, the rack 52 and pinion 50 are formed of a plastic impregnated with a lubricant, such as LNP RFL-4536 or similar materials.
The second access port 62 facilitates assembly of the foot pedal 14 during, for example, original manufacture or repair operations. In particular, the second access port 62 can be used to engage the rack 52 with pinion 50 in a desired manner when the base portion 20a and the pivoting portion 20b are interconnected. A user compresses the spring 60 via the access port 62 so that the spring 60 is in the position illustrated in
A circuit board 64 may house various electrical components including the processor 40, the antenna 38, and the transmitter programming interface 34. A shield 66 generally protects the internal components of the foot pedal from dust and debris during use of the system 10. As illustrated in
The shield 66 may be formed from various materials, including metals, plastics, combinations thereof, and the like. In some embodiments, the shield 66 may be comprised of aluminum, steel, or other similar materials to provide rigidity and stability. Alternatively, the shield 66 may be comprised of poly carbonate or other fiber materials to minimize interference with signals generated by the transmitter 24. In an exemplary implementation, the shield 66 is formed of a medium impact blended polymer, such as ABS (Acrylinitrile Butadiene Styrene) with anti-static properties to minimize the risk of undesirable electrical through one or more of the electrical components. By way of example, the shield 66 may be formed of CYCOLAC FR15 or similar materials.
The first access port 36 may provide access to the transmitter programming interface 34 or other internal components for purposes of programming the processor 40 or other components. As explained above, the transmitter programming interface 34 may include a rotary encoder or similar component for adjusting a frequency of communication signals transmitted between the foot pedal 14 and the receiver 16. The transmitter programming interface 34 may be placed on the circuit board 64 proximate the first access port 36 so that a user can actuate or connect to the transmitter programming interface 34 via the first access port 36.
Although the present technology has been described with reference to the preferred embodiments illustrated in the attached drawings, it is noted that equivalents may be employed and substitutions made herein without departing from the scope of the subject matter recited in the claims. It will be appreciated, for example, that either one of the rack 52 or the receiving bracket 58 may include a groove and the other a rail to enable sliding engagement between the rack 52 and the receiving bracket 58.
This is a continuation-in-part of application Ser. No. 12/113,719 filed May 1, 2008, which is hereby incorporated by reference herein.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 12116907 | May 2008 | US |
| Child | 13165731 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 12113719 | May 2008 | US |
| Child | 12116907 | US |
