Patent Application
20240091598
The invention pertains generally to racket stringing machines, and, more particularly, to string tensioning systems.
Racket stringing machines use string tensioning systems to stretch racket strings. Historically, such string tensioning mechanisms have been mechanical or electric.
Mechanical tensioning systems typically utilize a hand crank mechanism to stretch racket strings and a pre-compressed spring to determine when the racket strings have been stretched to a desired tension. For example, as illustrated in
Electric tensioning systems typically utilize an electric motor to stretch racket strings and a digital force gauge to determine when the racket strings have been stretched to a desired tension. For example, as illustrated in
Racket stringing machines that use mechanical tensioning systems have several advantages over their electric counterparts. First, the cost of mechanical tensioning systems is significantly lower than the cost of electric tensioners. Second, electrical tensioning mechanisms require a connection to a strong current source, such as a wall outlet, limiting their range of use.
Conversely, racket stringing machines that use electric tensioning systems have several advantages over their mechanical counterparts. First, the compressive properties of tension strings in mechanical tensioning systems change over time, so the tension springs must be intermittently recalibrated or replaced. Second, electric tensioning mechanisms can tension racket strings more accurately and consistently than mechanical tensioning systems. Third, electric tensioning systems often include various quick adjustment options such as a button to recreate the last selected tension.
Furthermore, many racket stringing machines provide a constant pull feature that is highly desired. This feature, available with electric tensioning systems, automatically tensions a racket string continuously after it is initially stretched. For example, once a racket string reaches its set tension, the motor stops pulling the tension head assembly. Within a few seconds, the string naturally stretches and its tension drops. The constant pull feature compensates for this drop in tension by slightly re-stretching the string to reach its desired tension once again. Depending on the characteristics of the string, this re-stretching process can be repeated several times.
There exists a long-felt need in the art for a string tensioning system that produces accurate and consistent string tensions, requires minimum maintenance, works with a weak current source, such as a battery, and provides quick adjustment options, all achieved in a low-cost manner.
The present disclosure satisfies the foregoing needs by providing, inter alia, a preset of racket stringing systems for addressing each of the foregoing desirable traits as well as methods of their use.
One aspect of the present invention is directed at a string tensioning system for use with racket stringing machines, the system comprising: a crank, a control module including a processor and memory, a force sensor, at least one racket stringing algorithm stored in the memory and executed in the processor, and a brake mechanism. The system may further comprise an electric tensioning mechanism. The system may further comprise a tension transfer bar. The force sensor may sense a force of the tension transfer bar. The incorporation of force sensor produces accurate and consistent string tensions.
The brake mechanism may be a clamp configured to stop brake disc rotation. The brake signal may be produced once the tension signal indicates that the tension of the racket string is equal to an intermediate tension of the racket string.
The system may further comprise a display module coupled to the control module. The system may further comprise an input module coupled to the control module and configured to receive user inputs, the user inputs including at least one of an intermediate tension of the racket string and a final tension of the racket string. The final tension may be equal to the intermediate tension.
The system may further comprise a battery. The system may operate without a connection to a strong current source. The electric tensioning mechanism may be an electric motor or an actuator. The system may provide a constant pull feature as found in high end racket stringing machines.
The system can, unexpectedly, use much smaller electric motors (or other electric tensioning mechanisms) than their electric counterparts. The advantages of incorporating small electric tensioning mechanisms into racket stringing machines include, but are not limited to, increased portability, lower production costs, lower power consumption, and lower maintenance costs.
Another aspect of the present invention is directed at a method of tensioning a racket string, the method comprising: fixing the first end of a racket string to a string holder of a string tensioning system and manually tensioning the racket string using a crank. The method may further comprise automatic tensioning of the racket string by an electric tensioning mechanism. The automatic tensioning of the racket string may be performed at least twice to produce a constant pull feature.
The foregoing summary, as well as the following detailed description of preferred variations of the invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there is shown in the drawings variations that are presently preferred. It should be understood, however, that the invention is not limited to the precise arrangements shown. In the drawings, where:
Where certain elements of these implementations can be partially or fully implemented using known components, only those portions of such known components that are necessary for an understanding of the present disclosure are described, and detailed descriptions of other portions of such known components are omitted so as not to obscure the disclosure.
In the present specification, an implementation showing a singular component should not be considered limiting; rather, the disclosure is intended to encompass other implementations including a plurality of the same component, and vice-versa, unless explicitly stated otherwise herein. Further, the present disclosure encompasses present and future known equivalents to the components referred to herein by way of illustration.
It will be recognized that while certain aspects of the technology are described in terms of a specific sequence of steps of a method, these descriptions are only illustrative of the broader methods of the disclosure and may be modified as required by the particular application. Certain steps may be rendered unnecessary or optional under certain circumstances. Additionally, certain steps or functionality may be added to the disclosed implementations, or the order of performance of two or more steps permuted. All such variations are considered to be encompassed within the disclosure disclosed and claimed herein.
Referring now to
The control module 342 may include a processor 348 and memory 350. The memory may contain at least one algorithm 252 that is executable in the processor. This algorithm 352 may be configured to enable the control module 342 to produce a brake signal based on the tension signal produced by the force sensor 344. For example, the system of
Alternatively, any of the control module functions described herein can be implemented using hardware (e.g., fixed logic circuitry such as integrated circuits), software, firmware, manual processing, or a combination thereof. Thus, the blocks discussed in the above disclosure generally represent hardware (e.g., fixed logic circuitry such as integrated circuits), software, firmware, or a combination thereof. In the instance of a hardware configuration, the various blocks discussed in the above disclosure may be implemented as integrated circuits along with other functionality. Such integrated circuits may include all of the functions of a given block, system, or circuit, or a portion of the functions of the block, system, or circuit. Further, elements of the blocks, systems, or circuits may be implemented across multiple integrated circuits. Such integrated circuits may comprise various integrated circuits, including, but not necessarily limited to: a monolithic integrated circuit, a flip chip integrated circuit, a multichip module integrated circuit, and/or a mixed signal integrated circuit. In the instance of a software implementation, the various blocks discussed in the above disclosure represent executable instructions (e.g., program code) that perform specified tasks when executed on a processor. These executable instructions can be stored in one or more tangible computer readable media. In some such instances, the entire system, block, or circuit may be implemented using its software or firmware equivalent. In other instances, one part of a given system, block, or circuit may be implemented in software or firmware, while other parts are implemented in hardware
The force sensor 344 may be coupled to the control module 342. The force sensor 344 may be any force sensor that is known in the art, including, but not limited to, Savio type, tension line, single point, s-type, load cell, and miniature force sensors. The force sensor may convert a measured force into an electrical tension signal that may be processed by the control module 342. For example, the system of
The brake mechanism 346 may be coupled to the control module 342. The brake mechanism 346 may be any brake mechanism that is known in the art, including, but not limited to, a clamp and an actuator. The brake mechanism 346 may activate upon receiving a brake signal from the control module 342, preventing further rotation of the crank. For example, the system of
The electrical components may further include an input module 354, a display module 356, a weak current source 362, and an electric tensioner 364.
The input module 354 may be coupled to the control module 342. In this embodiment, the memory 350 of the control module 342 may include an algorithm 358 configured to process user inputs received from the input module 354. In an alternative embodiment, the input module 354 is integrated into the control module 342. In yet another alternative embodiment, the input module 354 is integrated with the display module 356. The input module 354 may be configured to receive user inputs. User inputs may include an intermediate tension of the racket string and a desired tension of the racket string. The input module 354 may receive user inputs using any input method known in the art including, but not limited to, a keyboard, buttons, and a touch screen. For example,
The display module 356 may be coupled to the control module 342. In this embodiment, the memory 350 of the control module may include an algorithm 360 configured to display control parameters using the display module 356. In an alternative embodiment, the display module 356 is integrated into the control module 352. In yet another alternative embodiment, the display module 356 is integrated with the input module 354. The display module 356 may be configured to display control parameters. The control parameters may include an intermediate tension of the racket string, a final tension of the racket string, and/or a current tension of the racket string. The display module 356 may display control parameters using any display method known in the art including, but not limited to, LCD, LED, and OLED displays. For example,
The weak current source 362 may be coupled to the control module 342. The weak current source 362 may supply power directly to the control module 342, where the control module 342 diverts power to the other electrical components. In an alternative embodiment, the weak current source 362 supplies power directly to a plurality of electrical components. The weak current source 362 may be any type of portable energy storage that supplies power to the electrical components without a constant connection to a larger electrical grid, including, but not limited to, a battery or a battery pack. For example,
The electric tensioner 364 may be coupled to the control module 342. The electric tensioner 364 may be any known part or combination of parts that, ultimately, converts electric power into a mechanical motion that tensions a racket string, including, but not limited to, an electric motor or an actuator. For example,
According to an embodiment, the electric components of the system 340 are incorporated into racket stringing machines during the manufacturing process. According to another embodiment, the electric components of the system 340 system are sold as a kit. This kit may be retrofitted into existing racket stringing machines that use mechanical tensioning mechanisms. For example, a user may remove elements of the mechanical tensioning system and replace them with elements of the kit.
Referring now to
The crank 418 may rotate around the axel 419. The crank may be fixed to the disc brake 426 such that the crank 418 cannot rotate while the disc brake 426 is locked. In this embodiment, the crank 418 may be fixed to the gear 420 such that rotating the crank 418 rotates the gear 420 but rotating the gear 420 does not rotate the crank 418. This may be achieved through a two directional rachet connection between the crank 418 and gear 420. In an alternative embodiment, the crank 418 is fixed to the gear such that the gear 420 only rotates with the crank 418 and vice versa. As the crank 418 is rotated clockwise, the gear 420 rotates clockwise and pulls the entire tension head assembly 400 along the winding bar 402, tensioning the racket string 422.
In this embodiment, the force sensor 444 is a Savio type sensor, the brake mechanism 446 is a clamp, the weak current source 462 is a battery, and the electrical tensioning mechanism 464 is an electric motor.
According to an embodiment, the tension head assembly 400 with all attached components, including the system 440, are incorporated into racket stringing machines during the manufacturing process. According to another embodiment, the tension head assembly 400 with all attached components, including the system 400, are provided as a unit. This unit may be retrofitted into existing racket stringing machines that use mechanical tensioning mechanisms. For example, a mechanical tensioning mechanism can be removed from the winding bar 402 and replaced with this unit.
Referring now to
The crank 518 may rotate around the axel 519. The crank may be fixed to the disc brake 526 such that the crank 518 cannot rotate while the disc brake 526 is locked. As the crank 518 is rotated clockwise, the gear 520 rotates clockwise and pulls the entire tension head assembly 500 along the winding bar 502, tensioning the racket string 522.
In this embodiment, the force sensor 544 is a Savio type sensor, the brake mechanism 546 is a clamp, the weak current source 562 is a battery, and the electrical tensioning mechanism 564 is an actuator.
According to an embodiment, the tension head assembly 500, with all attached components, is incorporated into racket stringing machines during the manufacturing process. According to another embodiment, the tension head assembly 500, with all attached components, is provided as a unit. This unit may be retrofitted into existing racket stringing machines that use mechanical tensioning mechanisms. For example, a mechanical tensioning mechanism can be removed from the winding bar 502 and replaced with the unit.
The string tensioning systems of
These hybrid tensioning systems can, unexpectedly, use much smaller electric motors (or other electric tensioning mechanisms) than their electric counterparts. Electric tensioners require large, heavy-duty motors because the motors operate nearly continuously, performing large tensioning motions throughout the entire string tensioning process. Conversely, hybrid tensioning systems can use much smaller electric motors because the motors operate sporadically, only performing tiny corrective motions at the end of the string tensioning process, tensioning a racket string from an intermediate tension to the final tension. The ability to use smaller electric motors (or other electric tensioning mechanisms) results in many benefits:
Large motors are heavy and power hungry, requiring a constant connection to a strong current source, reducing the portability of electric tensioners. Conversely, small motors are light and energy efficient, able to work using solely a weak current source, increasing the portability of hybrid tensioning systems.
Large motors are expensive to produce, increasing the cost of electric tensioners. Conversely, small motors are inexpensive to produce, decreasing the cost of hybrid tensioning systems.
Large motors operate nearly continuously, increasing power and maintenance costs for electric tensioners. Conversely, small motors operate sporadically, decreasing power and maintenance costs for hybrid tensioning systems.
Now referring to
For embodiments of the invention that do not include an electric tensioner, the intermediate tension is the same as the final tension, both equal to the tension of the racket string after tensioning with the tension crank. For example, a user sets the intermediate tension and/or final tension to 45 lbs. He or she turns the tension crank until the tension of the racket string is equal to 45 lbs, activating the brake mechanism and preventing further crank rotation.
For embodiments of the invention that include an electric tensioner, the intermediate tension is equal to the tension of the racket string after tensioning with the tension crank and the final tension is equal to the tension of the racket string after tensioning with the electric tensioner. For example, a user sets the intermediate tension to 43 lbs and the final tension to 45 lbs. He or she turns the tension crank until the tension of the racket string is equal to 43 lbs, activating the brake mechanism and preventing further crank rotation. The electric tensioner then tensions the string up to the final tension of 45 lbs. The final tension may be equal to the intermediate tension, lower than the intermediate tension, or higher than the intermediate tension, according to user preference.
The steps depicted in
Now referring to
The steps depicted in
While the above detailed description has shown, described, and pointed out novel features of the disclosure as applied to various implementations, it will be understood that various omissions, substitutions, and changes in the form and details of the device or process illustrated may be made by those skilled in the art without departing from the disclosure. The foregoing description is of the best mode presently contemplated of carrying out the principles of the disclosure. This description is in no way meant to be limiting, but rather should be taken as illustrative of the general principles of the technology. The scope of the disclosure should be determined with reference to the claims.
