The present disclosure relates generally to a valve assembly for a suspension system of a bicycle, particularly to a valve assembly having a lock-out valve, and more particularly to a valve assembly having a rotary actuated lock-out valve.
A known bicycle suspension system is disclosed, for example, in U.S. Pat. No. 8,459,418.
While existing suspension systems for a bicycle may be suitable for their intended purpose, the art of bicycle suspensions systems, however, would be advanced by use of a rotary actuated lock-out valve as herein disclosed.
This background information is provided to reveal information believed by the applicant to be of possible relevance to the present invention. No admission is necessarily intended, nor should be construed, that any of the preceding information constitutes prior art against the present invention.
In an embodiment of the invention, a valve assembly for a bicycle suspension system includes a housing, a rotary valve disposed within the housing, and a rotational electro mechanical actuator (REMA) disposed within the housing. The housing is configured to house shock absorber fluid. The REMA is disposed in operable communication with the rotary valve. The housing, the rotary valve and the REMA define a plurality of fluid flow passages internal to the housing. The rotary valve and the REMA are each subject to contact with or immersion in the shock absorber fluid in the housing.
The above features and advantages and other features and advantages of the invention are readily apparent from the following detailed description of the invention when taken in connection with the accompanying drawings.
Referring to the non-limiting drawings wherein like elements are numbered alike in the accompanying Figures:
Although the following detailed description contains many specifics for the purposes of illustration, anyone of ordinary skill in the art will appreciate that many variations and alterations to the following details are within the scope of the invention. Accordingly, the following embodiments of the invention are set forth without any loss of generality to, and without imposing limitations upon, the claimed invention.
In an embodiment, a bi-stable rotary actuated valve assembly (valve assembly) in combination with an oil reservoir is fluidly connected via a flexible hose to a bicycle shock absorber unit. The ebb and flow of oil between the bicycle shock absorber unit and the oil reservoir is controlled by the valve assembly. The valve assembly includes: a housing that contains both a bi-stable REMA, and a rotary valve. The bi-stable REMA is an electromechanical unit having a magnet and electrical windings. The rotary valve is rotatable between open and closed positions via the bi-stable REMA (which receives operational signals via sensors on the bicycle). As the oil ebbs and flows in the shock absorbing system of the bicycle, it flows within the housing of the valve assembly through internal fluid flow ports, channels or paths, and through and around the electromechanical parts of the bi-stable REMA (that is, the bi-stable REMA, in addition to the rotary valve, is subject to contact with or immersion in the shock absorber oil in the housing of the valve assembly). The rotary valve is lockable in a closed position to provide for a stiff suspension to prevent bicycle “bobbing”, and lockable in an open position to provide dampened suspension to provide a smooth ride over rough terrain.
While embodiments are described herein with reference to a REMA, it will be appreciated that a plurality of REMAs may be employed for separate control functions, such as damping rebound control, low-speed damping compression control, and damping lock-out control, for example, which are discussed in more detail below. In an embodiment where a plurality of REMAs are employed, multiple valves are employed in a one-to-one relationship with the REMAs, where some of the REMAs may be servo or stepper motors that actuate an adjuster to a new fixed position. For example, to adjust for fade, instantaneous adjustment is not required, so a controller could sample every 10 seconds or so, and then facilitate movement of the adjuster to a new position if the temperature of the hydraulic fluid exceeds a certain threshold. Multiple REMAs are discussed in more detail below in connection with
While embodiments are described herein with reference to a bi-stable rotary solenoid, it will be appreciated that a REMA capable of proportional control could also be employed. Examples of this type of REMA would be a stepper motor, servo motor, rotary voice coil, Galvo motor, or proportional rotary solenoid.
While embodiments described herein depict bicycles suitable for mountain bike type applications, it will be appreciated that the disclosed invention is also applicable to other bicycle frame types, such as but not limited to commuter style bicycles, road bikes, e-bikes, or BMX style bicycles, for example. As such, the scope of the invention is not limited to only the bicycle frame embodiments disclosed herein, but encompass all bicycle frame types that fall within the ambit of the invention disclosed herein. It is also contemplated that the disclosed invention may also be usable on other types of vehicles. As such, the scope of the invention is not limited to bicycle use, but encompasses all vehicle uses that fall within the ambit of the invention disclosed herein.
In an embodiment, the bi-stable REMA (also herein referred to as an “actuator”) actuates a rotary valve immersed inside the oil of the shock absorber (also herein referred to as a “hydraulic damper unit”) to either allow flow or prohibit flow. The rotary valve is also herein referred to as a “lock-out valve”. In an embodiment, the lock-out valve rotates 45 degrees between open and closed positions, but may be configured to rotate through a different angle that is suitable for a purpose disclosed herein. The bi-stable REMA does not need power to maintain its position in the open and closed positions, substantially reducing power consumption compared to other types of actuators. By having the rotary valve immersed in the oil, it is not necessary to use a rubber dynamic seal between the rotary valve and the housing of the valve assembly, which would introduce a frictional load to the system that would slow down the response time of the REMA and increase power consumption. In contrast, a static seal between the actuator power supply wires and the housing of the valve assembly will not influence speed or power consumption of the REMA.
In an embodiment, the open-close/close-open response time is such that the lockout valve opens allowing hydraulic fluid to begin to flow before a rider can perceive that a bump was encountered. A fast reaction time enables the actuator to open the lockout valve before the hydraulic fluid pressure and flow become too large. In an embodiment, the actuator is strong enough so that it can operate up to a point that a blow off valve opens.
The valve assembly includes a compression damping assembly that is small enough so that power supply wires to the actuator may pass around the outside of the compression damping assembly. The off-set electrical connection to the actuator prevents the compression damping assembly from having to be rotationally aligned (or “clocked”) to the actuator, which would allow the wires to pass through the compression assembly. The off-set wires also negate the need to seal the wires from the compression damping assembly as the wires go around the compression damping assembly, not through the compression damping assembly.
In an embodiment, a microprocessor based controller disposed locally on the bicycle is disposed in signal communication with the various sensors and the bi-stable rotary actuated valve assembly to rapidly change the state of the rotary lock-out valve via the REMA depending on movements of the bicycle. In an embodiment, the microprocessor based controller comprises one or more microprocessors. In another embodiment, the microprocessor based controller comprises more than one microprocessor.
Use of an electro-mechanical control allows features of the bicycle to be performed with software, executable by the one or more of the microprocessors, that a user could activate or deactivate to adjust such features using the software. In particular, electro-mechanical control of low-speed compression, high-speed compression, low-speed rebound, high-speed rebound, and lock-out blow-off threshold can be used in a variety of combinations to provide improved ride control, such as for example, brake-dive control. Using various sensors including, but not limited to, accelerometers and a brake-activation sensors, it is possible to increase the low-speed compression damping in the fork and the low-speed rebound in the shock. In this way the weight-transfer to the front of the vehicle that occurs during braking can be reduced. A multi-position REMA may also be used for low speed damping control that provides proportional control of the valve to position the valve in one of a plurality of partially open/closed positions for providing a range of damping characteristics from soft to firm. In an embodiment, the REMA is a solenoid. In another embodiment, the REMA is a stepper motor.
In an embodiment, a temperature sensor is employed to measure the temperature of the hydraulic oil, which enables compensating for damping based on the temperature. Hydraulic fluid is very sensitive to temperature that may result in “fade” (reduced damping as the hydraulic fluid temperature increases), which is difficult to control with mechanical means. In an embodiment, fade is compensated for by measuring the temperature of the damping unit and adjusting the low-speed compression and low-speed rebound to give more consistent performance. Another manner of fade compensation is to adjust the front and rear gas springs as a function of temperature of the gas springs. By measuring the temperature of each gas spring, an air volume within the respective spring can be changed to adjust the behavior of the spring, or to transfer gas to a different chamber to accomplish the same. It will also be appreciated that changes in ambient temperature also have an effect on bicycle performance. As such, the same temperature sensors and adjustments could be employed to deal with ambient temperature changes. Other sensors, such as an air pressure sensor for example, may be employed to provide damping adjustment based on a change in air pressure of the air spring suspension unit.
In an embodiment, one or more of the above noted sensors are used to provide feedback regarding the state of the rider, such as standing up and sprinting versus seated pedaling. It can be appreciated that during seated pedaling, traction and comfort are both important, in addition to riding efficiency. In this situation it is desirable to have a “medium” amount of low-speed damping, but not necessarily locked out. However, during sprinting, it is desirable to have the suspension locked out as body motions tend to be exaggerated, which causes the bicycle to “bob” if the suspension is not locked out. Moreover, when the user is standing on the pedals, it is easier for the rider to adjust body positioning to move weight where it is needed for traction, or to absorb bumps using the body, so it is typically not necessary for the suspension to be soft in this instance.
In an embodiment, a bike speed sensor is employed that permits the actuation speed/mode of the valve assembly to be adjusted relative to bike speed for electric power consumption savings/economy, according to a defined algorithm executed by the controller.
In an embodiment, a bike inclination sensor is employed that permits the actuation speed/mode of the valve assembly to be adjusted relative to bike inclination for electric power consumption savings/economy, according to a defined algorithm executed by the controller. For example, uphill travel means relatively lower weight on the front wheel, so the valve assembly could be adjusted for lower power and speed of actuation. Downhill travel means relatively higher weight on the front wheel, so the valve assembly could be adjusted for higher power and speed of actuation. In an embodiment, a free-fall sensor is employed for detecting when the bike is jumping, so the valve assembly could be adjusted during a free-fall event for providing maximum speed of unlock with full power to the valve assembly. As used herein, a free-fall sensor (FFS) is an accelerometer used to detect if a bicycle is freely falling. The controller responsive to signals from the FFS can then apply appropriate adjustments to the damping characteristics of the shock absorber to absorb the shock of a sudden impending impact.
In an embodiment, a pressure sensor, weight sensor or strain gage sensor is employed and strategically disposed on the bicycle to sense the weight of a rider in a static and/or dynamic mode. In an embodiment, the controller is configured to be responsive to signals from the pressure/weight/strain gage sensor to adjust the damping characteristic of the suspension system according to a defined algorithm based on the rider's weight and/or riding dynamics.
In an embodiment, a pressure sensor, weight sensor or strain gage sensor is employed and strategically disposed on the bicycle to sense whether the rider is seated or standing on the pedals.
In an embodiment, a pressure sensor, weight sensor or strain gage sensor is employed and strategically disposed on the bicycle to sense whether the rider is pedaling or coasting.
In an embodiment, a brain sensor, or other brain sensing technology, is used to determine what the rider wants the shock absorber (damper) to do, and provides a signal to the controller that adjusts shock absorber accordingly. For example, the controller could be programmed to respond to a signal from the brain sensor that indicates that the user wants the valve to open.
In an embodiment, the brain sensor is integrated into the rider's helmet.
In an embodiment, the responsiveness of the suspension system, and more particularly the bi-stable rotary actuated valve assembly, is automatic absent any electronically controlled user interface, where the on-off state of the valve assembly is based on movement of the bicycle measured by at least one acceleration sensor. In an embodiment, if the bicycle is left inactive for more than a defined length of time, such as ten minutes for example, then the controller goes into sleep mode. In an embodiment, the controller is wireless enabled so that a user can adjust the sensitivity of lock timeout, or any other adjustable control setting, via a mobile phone app, or other wireless communication means. Other control algorithms may be implemented using the mobile phone app, or using an optional remote wireless user interface on a handlebar grip. A communication device such as a beeper or a multicolor LED may be included on the bicycle to communicate controller function and battery status.
Details of example embodiments will now be described with reference to the several figures provided herewith.
In the embodiment depicted in
Alternatively, a second tube (not shown), commonly referred to as a twin-tube arrangement, disposed either co-axially with or separated from the flexible hose or rigid tube, may be employed. In an embodiment, the second tube is rigid and arranged coaxially around the first rigid tube. Each tube flows oil in both directions (compression and rebound). In an embodiment, the first tube has a damping piston, usually but not necessarily solid, and may also contain high-speed or lock-out blow-off shims, and/or a rebound adjuster. The second tube routes fluid from the damping assembly (usually compression, rebound damping, and possibly lock-out occur in this damping assembly, but it could just be compression damping or compression damping and rebound) at a first end of the first tube to the second end of the first tube for a compression event (unless it is a “pull-shock,” then it is reversed). In a rebound event the second tube routes fluid from the second end of the first tube, to the damping assembly, and back into the first end of the first tube (unless it is a “pull-shock,” then it is reversed). Those skilled in the art commonly refer to this as a twin-tube damper.
Other aspects and features of the split shock 410 with the rotary actuated valve 420 will now be described with reference to
Various details of the split shock 410 are illustrated in expanded views in
Reference is now made to
The bladder 431 is arranged such that it surrounds the valve assembly 420 and the base valve 608. This arrangement allows compression damping adjusters (commonly known as low-speed compression adjusters, high-speed compression adjusters, and lock-out threshold adjusters) to be easily employed such that they do not have to pass through or around the valve 420 or IFP, which greatly reduces complexity. The base valve assembly 608 is made small enough so that the power supply wires 432 to the REMA 424 may pass around the outside of the compression damping valve 436 and other internal components 440. This prevents the base valve 608 from having to be rotationally aligned (or “clocked”) to the REMA 424 to allow the wires 432 to pass through the base valve assembly 608, and it also negates the need to seal the wires 432 to the base valve assembly 608. This arrangement also allows the adjusters to be independent of the electronic valve. For example, the adjusters may be configured to rotate relative to a fixed electronic valve. Alternatively, albeit less desirable because of the issue of twisting the electrical wires, the electronic valve itself may be configured to rotate to provide an adjustment feature, if the electronic valve were downstream of the compression assembly.
Reference is now made to
Another illustration of the flow of damping fluid is depicted in
In comparing the fluid flow paths of
Reference is now made to
With reference now to
With respect to all of the foregoing, in a first arrangement the valve assembly 420 is upstream of the compression assembly (fork or rear shock). The compression assembly is small enough for the offset wires to pass between the compression assembly and the damper housing (fork or rear shock). In this first arrangement a bladder is used for shaft-displacement and thermal compensation (fork or rear shock). In a second arrangement, there could be no compression damping “base valve”, and the lockout valve could be just upstream of the shaft-displacement reservoir. This second arrangement could use a bladder for a fork or rear shock, or an IFP for a rear shock. In a third arrangement, a rear shock could have the valve downstream of the compression damping circuit and could use an IFP for shaft-displacement and thermal compensation. For the above mentioned second and third arrangements, rather than the compression assembly being small enough for the offset wires to bypass, a fluid communication port to the IFP may be provided that is made small enough so the offset wires can bypass this fluid communication port and exit the valve housing. The fluid communication port to the IFP would be necessary regardless of whether there is a base valve or not. With regard to a fluid communication port, there is no functional difference between a damper with a base valve upstream of the electronic valve, and a damper with no base valve.
In an embodiment, the housing of the valve assembly 420 may be made of molded plastic, and the electrical wires 432 of the valve assembly 420 that provide power to actuate the REMA 424 may be molded into the molded plastic housing, which provides an advantage of sealing the electrical wires without the need for a separate sealing member.
Regarding the use of a bladder versus an IFP, a fork or shock damper only requires a bladder or an IFP, but not both. The bladder arrangement allows the hydraulic fluid to be routed so that it enters from one end and exits at the other. The bladder arrangement is an annular arrangement that may be more difficult to implement with an IFP. However, an IFP can be annular, but fluid cannot enter from one side of it and exit from the other. While embodiments disclosed herein may be best suited for either a bladder arrangement or an IFP arrangement, the scope of the invention disclosed herein is not limited to just one arrangement or the other, and is intended to encompass both arrangements.
From the foregoing, it will be appreciated that embodiments of the invention may be implemented on front fork or rear shock suspension systems. Typically, a front damper features an externally adjustable low-speed compression adjuster, external low-speed rebound adjuster, and air spring pressure adjuster. As previously mentioned, the front damper can also have any number of other mechanical adjusters (high speed compression, and lockout threshold, for example). In an embodiment, the shock only has low-speed rebound damping and air spring adjustments as mechanical features, as it would be difficult to access an external low-speed compression adjuster with the reservoir hidden in the top tube. However, such access issues may not be present in a front fork that does not utilize a common reservoir with the rear shock, thereby enabling a low speed compression adjuster on the front fork, which is something that cross country race users can appreciate.
An embodiment of the invention may be embodied in the form of computer-implemented processes and apparatuses for practicing those processes. The present invention may also be embodied in the form of a computer program product having computer program code containing instructions embodied in tangible media, such as floppy diskettes, CD-ROMs, hard drives, USB (universal serial bus) drives, or any other computer readable storage medium, such as random access memory (RAM), read only memory (ROM), erasable programmable read only memory (EPROM), electrically erasable programmable read only memory (EEPROM), or flash memory, for example, wherein, when the computer program code is loaded into and executed by a computer, the computer becomes an apparatus for practicing the invention. The present invention may also be embodied in the form of computer program code, for example, whether stored in a storage medium, loaded into and/or executed by a computer, or transmitted over some transmission medium, such as over electrical wiring or cabling, through fiber optics, or via electromagnetic radiation, wherein when the computer program code is loaded into and executed by a computer, the computer becomes an apparatus for practicing the invention. When implemented on a general-purpose microprocessor, the computer program code segments configure the microprocessor to create specific logic circuits. A technical effect of the executable instructions is to automatically activate/deactivate a bi-stable rotary actuated valve of a bicycle suspension system to adjust the damping thereof in response to sensor signals indicative of bicycle motion
In an embodiment where the suspension system disclosed herein is connected to an e-bike drive system, the controller may be configured to receive data (e.g. CAN BUS data) from the e-bike drive system, where such data would be taken into consideration by executable instructions executed by the controller as to how the suspension system is adjusted.
As disclosed, some embodiments of the invention may include some of the following advantages: high speed damping adjustment of a bicycle suspension system at a rapid rate of adjustment that is faster than a rider is capable of perceiving; high speed damping adjustment of a bicycle suspension system capable of reacting to individual bumps in the terrain; and, high speed damping adjustment of a bicycle suspension system capable of relatively low or zero power consumption by using a bi-stable actuator that does not require power to maintain its position in the open and closed positions.
While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best or only mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another. Furthermore, the use of the terms a, an, etc. do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item.
This application claims the benefit of U.S. Provisional Application Ser. No. 62/086,370 filed Dec. 2, 2014, which is incorporated herein by reference in its entirety.
Number | Date | Country | |
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62086370 | Dec 2014 | US |