It should be noted that the figures are not drawn to scale and that elements of similar structures or functions are generally represented by like reference numerals for illustrative purposes throughout the figures. It also should be noted that the figures are only intended to facilitate the description of the preferred embodiments. The figures do not illustrate every aspect of the described embodiments and do not limit the scope of the present disclosure.
The present disclosure illustrates and describes example designs and demonstrates the example implementations of various example embodiments of a gravity balancing monopod 100. Some examples can use a nearly-constant force spring to offset the gravity loading of a load fixed to an end of the monopod 100 as describe herein. Various embodiments comprise a spring in the monopod 100 that can be designed to provide a nearly constant force about a force that can be manually set by the user (the nominal force). An embodiment of this design uses a gas spring where the pressure inside one or more chamber can be manually set by the user through adjusting a valve connected to a contained high pressure source such as a carbon dioxide tank.
In one preferred embodiment, the design comprises a gas spring with adjustable pressure, but other embodiments can comprise one or more mechanical spring with a set preload, and the like. The spring assembly of such embodiments can be designed and configured in various suitable ways, including various suitable configurations of the stroke, spring bore, allowable deviation from constant force, and the like.
Turning to
For example, in the embodiments 100A, 100B a gravity balanced monopod 100 is shown comprising a first, second and third segment 120A, 120B, 120C with the first segment 120A being at the top-end 111, the third segment 120C being at the bottom-end 112, and the second segment 120B being disposed between the first and third segments 120A, 120B. In these examples, the first segment 120A has a larger diameter than the second segment 120B, and the second segment 120B has a larger diameter than the third segment 120C. Such a configuration can allow for the third segment 120C to slidably telescope within the second segment 120B, and for the second segment 120B to slidably telescope within the first segment 120A.
Although the examples shown herein illustrate example embodiments having successively smaller segments 120 toward the bottom-end 112, other configurations are within the scope and spirit of the present disclosure. For example, further embodiments can include successively larger segments 120 toward the bottom-end 112; a larger middle segment 120B between smaller end segments 120A, 120C; a smaller middle segment 120B between larger end segments 120A, 120C, and the like. Additionally, while examples shown herein illustrate monopods 100 having two or three segments 120, it should be clear that further embodiments can include any suitable plurality of segments 120 including four, five, six, seven, eight, and the like.
In various embodiments, a gravity balanced monopod 100 can be configured for assisting with the lifting of loads. In some embodiments, the monopod 100 can provide the ability for an operator to counteract a desired load through pushing on the ground. For example, as described in more detail herein, the monopod 100 can use a gas spring to provide a substantially constant force that can be set by the operator over a set range of motion. The telescoping segments 120 can allow the monopod 100 to move the constant force range as desired.
An implementation of various embodiments is to hold a work-tool. In this event, the target force output from the monopod 100 can be set to counteract the gravity load associated with the work-tool or other load. For example,
In such examples, the monopod 100 can allow a user to naturally manipulate and operate the work-tool 101 without having to bear the weight of the work-tool 101. In other words, the monopod 100 can take the weight of the work-tool 101 and the range of motion provided by the telescoping segments 120 allows for natural manipulation and operation of the work-tool 100 within a desired target work area.
The monopod 100 can extend to a foot 130 at the bottom-end 112, which can be configured to engage the ground or other surface below a target work area. In some embodiments, the foot 130 can comprise a rubber bumper or other suitable structure configured to engage a surface. In further embodiments, the foot 130 can comprise other suitable structures such as tripod, pin, bearing, wheel, or the like. The foot 130 can coupled to the ground directly, or via a structure, or can engage the ground but be movable. In some embodiments, the bottom-end 112 can be coupled to a user via a harness or other system.
Additionally, while a hammer drill work-tool 101 is shown in
Turning to
As illustrated in
The volume V can expand or contract based on various factors including force exerted on the shaft 227 (and piston 226) and force exerted on the top-end 111. For example, where a work-tool 101 exerts a downward force on the top-end 111 (e.g., as illustrated in
Accordingly, the amount of a gas within the cavity 224 between the wall 223 and the piston 226 can define the volume V that results when a given load is applied to the top-end 111 of the monopod 100 (e.g., by a work-tool 101 or the like). In other words, the amount of gas within the cavity 224 between the wall 223 and the piston 226 can dictate the length at which the monopod 100 assumes a compression equilibrium under the load applied to the top-end 111. However, as discussed in more detail herein, the compressibility of gas will allow for movement of the load (e.g., the work-tool 101) by a user within a range of the equilibrium length or height.
The stroke of one or more pistons 226 within a respective cavity 224 can correlate to how far the monopod 100 provides gravity balance functionality. Different applications, or user preferences, may involve different stroke lengths, but some preferred embodiments include a stroke of 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, or 34 inches. Accordingly, preferred embodiments of a monopod 100 can be configured to have a stroke within the range of any of such strokes.
Fluid 225 can be introduced into or removed from the cavity 224 in various suitable ways. For example,
For example, one or more pressures in the segments 120 can be modified in a number of ways. In the example of
In various embodiments, the fluid source 253 can be completely self-contained within the monopod 100. In other words, the fluid source 253 can part of a unitary structure of the monopod 100 in contrast to an external fluid source such as an external compressor system or the like. Stated another way, the fluid source 253 of various embodiments can comprise a limited volume of fluid in contrast to rechargeable external fluid source such as an external compressor system.
In another embodiment, the pressure can also be supplied by a hand pump (e.g., a portable bike pump, or the like). Another embodiment can provide the operator with a regulator that has a series of pressure settings that correspond to regulator settings where the operator can manually set the amount of force required by the task. Yet another embodiment can involve a valve that controls gas flow from a high pressure source to provide a desired output force.
Additionally, any suitable fluid can be used in various embodiments, including gas fluids such as carbon dioxide, air, helium, nitrogen, argon, and the like. Additionally, further embodiments can use liquid fluids such as water, oil, and the like. Some preferred embodiments include the use of standard (e.g., ISO standard) fluid cartridges including an 8 gram, 12 gram, 16 gram, 24 gram, or 88 gram carbon dioxide cylinder.
In some embodiments of a gas spring, it can be desirable for the gas pressure to remain substantially constant or within a narrow range at fully compressed and fully extended configurations. The change in the gas pressure in a passive fixed chamber can be dictated by the ratio of the gas volumes in the two configurations. In some embodiments, the ratio of volumes (Vextend to Vcollapse) can be large and can lead to a large change in operating pressure, which can be undesirable in certain embodiments. To combat this, further embodiments can include a larger nominal volume that allows the effect of the change in volume to be reduced and result in a smaller volume change.
For example,
However,
Although
Other embodiments can comprise alternative and/or additional components to reduce the pressure variation throughout the stroke. One example can include reducing the stroke of the one or more segments 120 that define the gravity balanced section. Other embodiments can include one or more subsequent segment 120 including an internal cavity and/or a large bore. Such examples can enable a smaller reduction in volume for the same stroke by maintaining the fixed volume in smaller package.
For example,
In this example, the shaft 227 of the second segment 120B is configured to slidably engage a seal 428 (e.g., a gasket) at the end-cap 228 of the first segment 120, which allows fluid to be held within the first and second cavity 224, 424 under pressure. The total volume within the first and second cavity 224, 424 is defined by the second volume V2 and by the first volume V1, which is a larger volume V11 in the expanded configuration of
In other embodiments, the bore or diameter of the segments 120 of a gas spring defined by the monopod 100 can be modified to target a desired operating pressure for a desired operating range. For a fixed operating load, in some embodiments, a larger cylinder bore can allow for lower chamber pressures or can allow for such embodiments to be used for higher loads.
Although various examples embodiments of a monopod 100 having a plurality of segments 120 that can define a fluid spring are shown, this should not be construed to be limiting on the wide variety of embodiments within the scope and spirit of this disclosure that can be employed for defining a fluid spring. For example, some embodiments of a monopod 100 can have any suitable plurality of segments 120 with such segments defining or not defining a cavity in various suitable configurations as illustrated in
Accordingly, segments 120 can define movable fluid cavities in various suitable ways. For example, two or more segments 120 can operate as a gas spring found in conventional lift gate operations. These gas springs can comprise a single sealed chamber with a shaft 227 (e.g., as shown in
As discussed herein, various embodiments of a monopod 100 can be optimized to specify the spring design specifics as described herein above such as stroke, cylinder bore, and pressure variation. In some implementations the monopod 100 can be configured for use over a larger range of motion. In this event, we will consider an example embodiment that is designed for a 12 inch stroke of gravity balance. This example monopod 100 can be configured to move freely through the 12 inch stroke, but if a work-tool 101 (
This example embodiment 100F includes a mechanical telescoping feature through a series of clamps 510 that allows the user to manually set the range of where the 12 inches of gravity balanced functionality can exist. For example, the clamps 510 can include a collar 511 that surrounds a portion of a respective segment 120, with a knob 512 that can be tightened to fix the collar 511 in place. In other words, the clamps 510 can be movable along the length of a respective segment 120 when loose and then can be fixed in a position on the segment 120 to adjust the range of motion of the segments 120.
Some embodiments can include a telescoping capability that engages and disengages with the press of a button, or the like. For example, in one embodiment, a second segment 120B can be locked within a first segment 120A at a given extension configuration (e.g., in a compressed or extended configuration) and unlocked by pressing a button (e.g., like a telescoping umbrella or retracting ballpoint pen). In another example, compressing a second segment 120B within a first segment 120A can cause the segments 120 to lock at a certain position, and the first and second segment 120A, 120B can be unlocked by depressing the segments 120 past this locked position.
Such examples can apply to single pairs of segments or can be applied to a plurality of pairs of segments at the same time. For example, a single button can unlock a plurality of locked segment pairs or further compressing a locked monopod 100 past a locked configuration can unlock a plurality of locked segment pairs. Yet another embodiment involves a controlled telescoping capability where the telescoping capability is controlled by one or more motor, ratchet, or the like.
To help minimize the amount of compressed gas needed to operate over long working shifts, some embodiments of the monopod 100 can include an apparatus to lock the constant force spring in its retracted position. This can effectively minimize the length of the device for easy maneuvering in tight quarters. This lock can be similar to the telescoping locking mechanisms discussed above or can comprise a valve, which when closed, prevents the flow of fluid in or out of one or more fluid sources 253 or one or more cavities defined by one or more segment 120. One other embodiment of a shaft lock comprises a hydraulic shaft collar that can prevent the sliding of the cylinder shaft during transport. Similar locking mechanisms such as electromechanical brakes can also be utilized, which may allow locking at any point within the stroke of the monopod 100 and not just at specific points of the stroke of one or more segments 120.
An end effector can be coupled to an end 111, 112 of a monopod 100 in various embodiments, which can be tailored to the user's application. In such embodiments, various end effectors can attach to the monopod 100 through a fixture such as a threaded rod of a known thread pattern. In the example embodiments of
One embodiment can affix the gravity balanced monopod 100 to a waist belt while other embodiments may affix the monopod 100 to a torso harness to support with stability. Another embodiment of the monopod 100 may not be targeting constant force that offsets gravity of a load but that is some delta from this weight to provide a near constant upward or downward force from the connected load. Yet another embodiment can target a non-constant force output and instead be targeting a linear force profile through the stroke of the plurality of segments 120.
Turning to
A volume of fluid 225 can be disposed in the within a portion of a cavity 224 between a wall 223 of the first segment 120A and a piston 226 of the second segment 120B. A shaft 227 can extend from the piston 226 and out an end-cap 228 of the first segment 120A. The piston 226 can slidably reside within the cavity 224, which can change the volume of the cavity 224 in which the fluid 225 resides.
The monopod 100 further comprises a fluid assembly 250 having a housing 251, a fluid-control interface 252 and fluid source 253 that is operable to store fluid 225. Fluid can pass between the fluid source 253 and the cavity 224 via a fluid line 254 and under the control of the fluid-control interface 252, which in this example comprises a valve-control knob. Additionally, this example embodiment 100G illustrates an example wherein the fluid line 254 is at least longer than the first and second segment 120A, 120B combined in the compressed configuration. Additionally, the fluid line 254 is shown being disposed exclusively external to the body 110 of the monopod 100 aside from a small portion interfacing with the cavity 224.
Turning to
The first segment 120A defines a first cavity 224 in which the second segment 120B slidably resides, including a portion in which fluid resides between a first wall 223 of the first segment 120A, and a piston or second-segment end 226. The second segment 120B comprises a shaft 227 that extends out a first-segment end-cap 228.
The second segment 120B defines a second cavity 824 in which the third segment 120C slidably resides, including a portion in which fluid resides between a second internal wall 823 of the second segment 120B, and a piston or third-segment end 826. The third segment 120C comprises a shaft 827 that extends out a second-segment end-cap 828 and terminates at a foot 130 at the bottom-end 112.
A stop 910 is disposed on the shaft 227 of the second segment 120B and is configured to engage the first-segment end-cap 228, which includes a first guard 915 that encircles the shaft 227 of the second segment 120B. The second-segment end-cap 828 includes a second guard 920 that encircles the shaft 827 of the third segment 120C.
The monopod 100 further comprises a fluid assembly 250 having a housing 251, a fluid-control interface 252 and a fluid source 253. Fluid can pass between the fluid source 253 and the cavity 224 via a fluid line 254 and under the control of the fluid-control interface 252, which in this example comprises a valve-control knob. In this example, the fluid line 254 extends from the housing 251 disposed within the base 121 to a line port 954 proximate to the bottom-end 112, which is configured to introduce and/or remove fluid from the third cavity 844. In this example, the fluid line 254 extends through the base 121, out the wall 223, into the first cavity 224, though the second internal wall 823 of the second segment 120B, into the second cavity 824, through the piston or third-segment end 826 of the third segment 120C and into the third cavity 844.
In various embodiments, the third cavity 844 can communicate with the first and second cavity 224, 824 such that fluid introduced to the third cavity 844 from the line port 954 can pass into the first and second cavity 224, 824. In some embodiments, the fluid line 254 can comprise ports along the length of the fluid line 254 which are configured to separately communicate fluid into and/or out of the first, second and third cavities 224, 824, 826, even in embodiments where the first, second and third cavities 224, 824, 826 are not configured to directly communicate fluid between each other.
Additionally, as shown in
Turning to
For example, as discussed herein, various types of work-tools 101 or other loads can be coupled to the top-end 111 of a monopod 100 and the foot 130 or other portion of the bottom-end 112 of the monopod 100 can be engaged with the ground or other suitable surface. In various embodiments, the monopod 100 can be configured to operate substantially parallel to the force of gravity; however, maintaining the body axis Y in an exactly parallel orientation to the force of gravity may not be necessary or desirable. For example, in various embodiments, the foot 130 or other portion of the bottom-end 112 can sufficiently engage the ground or other surface such that the bottom-end 112 remains engaged with the ground even when the body axis Y is not exactly parallel with the force of gravity.
Accordingly, in various embodiments, the monopod 100 can be configured to operate within an area or radius off parallel-to-gravity based on the ability of the bottom-end 112 to remain engaged. In other words, the monopod 100 can be operated at angles away from parallel-to-gravity until such an angle causes the bottom-end to slide, dislodge or otherwise undesirably move on or lose contact with the ground. Such angles can depend on the structure of the bottom-end 112 and on the surface being engaged. For example, in some embodiments, a maximum angle away from parallel-to-gravity can include 1°, 2°, 3°, 4°, 5°, 10°, 15°, 20°, 25°, 35°, 40° or the like.
Returning to the method 1000 of
For example, the fluid pressure and/or amount of fluid in the monopod 100 can be increased via a fluid-control interface 252 of a fluid assembly 250 (see e.g.,
Additionally, while the example method 1000 includes pressurizing the monopod 100 up to a desired pressure, in some examples, the monopod can be pressurized and de-pressurized for reach such a desired pressure. For example, where a desired gravity load offset is exceeded by over-pressurization, fluid can be released to bring the pressure down and to reach the desired gravity load offset.
Also, such a desired gravity load offset can be zero, positive or negative. In other words, a desired gravity load can include a positive upward force generated by an offset force greater than the gravity load; a balancing force generated by an offset force that is equal to the gravity load; or an incomplete load bearing force generated by an offset force that is less than the gravity load.
Returning to the method 1000 of
Returning again to the method 1000, in block 1070, the monopod 100 is depressurized and/or the amount of fluid within the monopod 100 is decreased, and in block 1080, the work-tool 101 is removed or de-coupled from the top-end 111 of the monopod 100. For example, once a user has completed work with the work-tool 101, the user can de-pressurize the monopod 100 and remove the work-tool 101 so that the work-tool 101 and monopod 100 can be stored, transported or the like.
Removability of the work-tool 101 can be desirable so that the work-tool 101 can be used independently of the monopod 100 and so that the monopod 100 can be used with different work-tools 101 or other loads. Additionally, the ability to select different pressures for a monopod 100 and different desired gravity load offsets can be desirable so that a user can accommodate a wide variety of work-tools 101 that can be coupled with the monopod 100 under various working conditions in different working environments.
De-pressurization of the monopod 100 can be done in various suitable ways including via venting fluid into the environment or via venting fluid back into the fluid source 253 or other storage container. Such de-pressurization can occur via the fluid-control interface 252 of the fluid assembly 250 or the like.
The described embodiments are susceptible to various modifications and alternative forms, and specific examples thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the described embodiments are not to be limited to the particular forms or methods disclosed, but to the contrary, the present disclosure is to cover all modifications, equivalents, and alternatives.
This application is a non-provisional of U.S. Provisional Application Ser. No. 62/293,657 filed Feb. 10, 2016, which application is hereby incorporated herein by reference in its entirety and for all purposes.
Number | Date | Country | |
---|---|---|---|
62293657 | Feb 2016 | US |