This disclosure relates to hand tool accessories, and in particular to ergonomic holders for hand tools.
Hand tools of a seemingly infinite variety have been developed for many purposes, and are currently used by individuals ranging in skill level from craftsmen with many years of trade experience to untrained persons needing to accomplish a simple task around the house. One thing many hand tools have in common, however, is that prolonged use and repeated manipulation of a hand tool, such as a screwdriver, a ratchet, a paintbrush, and so forth, tends to cause user fatigue. This is commonly because the same muscles and joints that are used to manipulate a hand tool, generally those of the user's fingers and/or wrist, also bear the weight of the hand tool. Use of a paintbrush, for example, generally involves not only supporting a wet brush made heavy with paint, but also requires repetitive back-and-forth movement of the user's wrist and/or force applied with the fingers. Also, the orientation at which a tool must be held when used, such as a paintbrush when applying paint to a surface, often requires the user's hand to be at an angle with respect to the user's wrist, further contributing to user discomfort.
Illustrative embodiments of an ergonomic hand tool holder are disclosed. In general, the ergonomic hand tool holders disclosed herein support a hand tool (such as a paintbrush), or a portion thereof (such as a paintbrush handle, or a paintbrush head), for use, while being received comfortably in a user's hand when it is in a natural resting angle with respect to the wrist. To this end, the holders define hand rest areas adapted to engage and rest against the “saddle” of a user's hand (that is, the region of the hand between a user's thumb and forefinger, and the areas surrounding this region on the front and back of a user's hand), when the holder is held. Accordingly, when the holder is held with the tool in position use, the weight of the holder and its supported load is distributed to the dorsal saddle area of the user's hand, allowing the user's arm to bear the weight, while the user's wrist and fingers guide, rather than carry, the tool.
In some embodiments, the ergonomic holder includes a body having a tool support portion adapted to support at least a portion of a hand tool, with the working end of the tool oriented generally forward from a forward end region of the body. In such embodiments, the body further includes forefinger and thumb rest areas respectively defined by outwardly-facing, usually concave surfaces of opposing side regions of the body, and a first hand rest area defined by a bottom-facing surface of the body disposed rearward of the side regions. A brace portion extends downwardly from a bottom region of the body and includes a second hand rest area defined by a rearward-facing surface of the brace portion. The first and second hand rest areas, respectively, engage the dorsal and palmar saddle areas of a user's hand when the user holds the holder with the forefinger and thumb engaging the forefinger and thumb rest areas.
In some embodiments, the brace portion forms a handgrip that a user may grasp in a pistol grip when the holder is so held, that is, with one or more of the user's middle, ring, and pinky fingers engaging the handgrip to urge the second hand rest area against the user's palm and/or palmar saddle area.
In some embodiments, the angle and/or distance between the first and second hand rest areas is adjustable, such as to accommodate different hand sizes or proportions. In embodiments that include a handgrip, the adjustability may be accomplished by a handgrip adapted to articulate. In some of such embodiments, the handgrip includes a proximal portion and a distal portion, wherein the distal portion articulates with the proximal portion, such as by means of a bendable connecting strut, a hinged area connecting the portions, and so forth. In such embodiments, the proximal and distal portions may be wholly or partially spaced from each other by an intermediate section having a greater degree of flexibility than the surrounding sections. Some of such embodiments may include a locking mechanism adapted to selectively retain the handgrip, or a section thereof, in a desired position with respect to the body, to maintain a selected distance or angle between the first and second hand rest areas.
Some embodiments include a counterweight device adapted to balance the combined weight of the holder, and a hand tool held thereby, over or near to the dorsal saddle area of a user's hand when the holder is held. In some counterweight embodiments, the weight of the counterweight device is adjustable, such as by being adapted to detachably accept counterweights of varying weight.
The counterweight may be selectively attached to at least a portion of the hand tool via a wide variety of means. For example, at least a portion of the counterweight may be complimentarily threaded with threads in a hole formed in the body of the hand tool and attached by screwing the threaded portion of the counterweight into the hole. Other suitable means for attaching the counterweight to hand tool include magnets or magnetic fasteners, adhesives, hook-and-loop fasteners, and straps or cord to bind the counterweight to hand tool. In some embodiments, the counterweight device is selectively attachable to the hand tool via a clip-on or similar mechanism. In others of such embodiments, the counterweight is attached to or integral with the body of a holder, such as by extending rearward from a rearward end region of the body.
In some embodiments, the tool support device is disposed on the top and/or forward end region(s) of the body. Some of such embodiments include an open-ended channel formed by a pair of longitudinal walls disposed along the top region of the body, wherein the channel is adapted to receive at least a portion of the handle of the tool. Such embodiments may include a retaining device to retain the portion of the tool received in the channel. Others of such embodiments may include a mounting section to which at least a portion of a hand tool may be mounted. Such embodiments may be configured to accept a variety of detachable tool portions, such as paintbrush heads of different sizes and configurations.
The illustrative embodiments disclosed herein are shown and discussed with respect to a paintbrush, as a non limiting example of a hand tool, for the sake of ease of explanation. However, the principles of construction and operation explained and illustrated herein may be adapted to a wide range of hand tools, including screwdrivers, ratchets, trowels and other surface preparation tools, gardening tools, culinary and kitchen utensils, and so forth, without departing from the spirit and scope of this disclosure, which is intended to encompass such variations.
The concepts, features, methods, and component configurations briefly described above are clarified with reference to the accompanying drawings and detailed description below.
In this description, orientational and directional terms such as “left,” “right,” “front,” “rear,” “forward,” “rearward,” “top,” “bottom,” and so forth, are used for clarity of illustration and generally refer to the relative positions of components and other objects illustrated in the drawings, but are not intended to be limiting, as the ergonomic tool holders (and components thereof) are not restricted to the orientations and positions shown in the drawings.
Body 102 of holder 100 includes a tool support portion 106 adapted to receive and support a hand tool, or at least a portion thereof, with the working end of the tool oriented generally forward from a forward end region of the body. For example, tool support portion 106 of holder 100 captures and holds the handle 12 and part of the neck 14 of paintbrush 10, with the head 16 of the paintbrush protruding from the front end of holder 100.
More specifically, and with reference to
However, as will become clear from the following description, the tool support portion of an ergonomic tool holder according to the present disclosure may be in any suitable configuration, and located on any desired region of the holder. Further, although the retaining means incorporated in tool support portion 106 is in the form of a pair of flexible foam pads, any manner of retaining device may be used to retain the portion of the tool received by or within the tool support portion. For example, in an embodiment that includes a tool support portion having a channel, such as in holder 100, a brush handle (or other hand tool portion) may be retained therein by means including one or more mechanical clamps to engage the hand tool, springs, locks, straps, magnets, inflatable bladder, snap-in shell, and so forth, as well as combinations thereof.
In embodiments in which a press fit between a pair of walls is used (as shown), different configurations of materials may be used instead of foam pads, such as ribbed, dimpled, or other textured surfaces, which may be formed of the walls themselves or mounted (e.g. detachably or permanently) thereto. Moreover, although the floor 114 of the channel 106 of body 102 is shown to be spaced away from handle 12 of paintbrush 10, other configurations may include a channel floor, or floor portion, configured to engage a portion of the hand tool received in the channel, such as to provide a support and/or retaining means. Alternatively, as noted above, the illustrated configuration may allow the user the option to urge the handle 12 further downward in the channel than as shown, such as to use the floor thereof to brace the handle in a desired position within the channel.
Generally, a user's hand 20 includes a palm 22 to which is connected a thumb 24, a forefinger 26, a middle finger 28, a ring finger 30, and a pinky finger 32. A web of muscles connects the base of the thumb and forefinger, and creates a fleshy pad in the form of a thenar eminence (represented generally at 34) on the side of the palm of a user's hand, and another fleshy pad in the form of a first dorsal interrosseal area (represented generally at 36) on the thumb side of the back of the user's hand. The region of flesh 38 between the thumb and forefinger, as well as the fleshy pads 34, 36 on either side of the user's hand, are collectively referred to herein as the “saddle” of the user's hand, indicated generally at 40. Additionally, the first dorsal interrosseal area 36 is referred to herein as the “dorsal saddle area,” and the thenar eminence 34 is referred to herein as the “palmar saddle area,” of a user's hand.
With the aforementioned anatomical explanation in mind, the illustrative embodiments of the ergonomic hand tool holders disclosed herein may be thought of as configured to rest the bulk of the holder against the dorsal saddle area of a user's hand, when the user's hand is oriented with the dorsal saddle area upward, with the body and other components of the hand tool holder adapted to receive a user's fingers and/or other hand areas to stabilize, the holder in position.
For example, with reference to
Although not required to all embodiments, in the illustrated embodiment, forefinger and thumb rest areas 120 are each further defined by upper and lower ridges 126, 128 that may provide a tactile guide for proper positioning of a user's thumb and forefinger when holding the holder 100. Not only do the forefinger and thumb rest areas 120 allow the small muscles, tendons, and joints of the fingers to relax while the holder is held, but the rest areas are positioned to allow the forward end region of the holder to be moved easily with only slight pressure from the user's forefinger and thumb to guide the tool supported in the holder during use.
Further, body 102 and handgrip 104 of holder 100 are shaped to interfit with the saddle area 40 of a user's hand, generally by means of first and second hand rest areas 130, 132. More specifically, first hand rest area 130, which is shown to be defined by a bottom-facing, convex surface 134 of body 102 that is disposed rearward of the forefinger and thumb rest areas 120, is adapted to engage and rest against the dorsal saddle area 36 of a user's hand 20 when the holder is held with the user's forefinger 26 and thumb 24 engaging the forefinger and thumb rest areas 120. Additionally, second hand rest area 132 is shown to be defined by a rearward-facing, convex surface 136 of handgrip 104, which is adapted to engage and rest against the palmar saddle area 34 of the user's hand 20 when the holder is so held. Also, although not required to all embodiments, body 102 of holder 100 defines a continuous intermediate surface 138 extending between the first and second hand rest areas 132, 134, which is adapted to engage the region 38 of a user's hand 20 between the forefinger and thumb, when the holder is so held.
Handgrip 104 of holder 100 further includes a grip area 140 defined by a forward-facing, convex surface 142 of the handgrip, such that the handgrip 104 is adapted to be grasped in a pistol grip, that is, with one or more of the user's middle (28), ring (30), and pinky (32) fingers engaging the grip area 140 when the holder is held as described above.
Like the forefinger and thumb rest areas 120, the various hand- and finger-engaging regions of holder 100 are shown as generally smooth, continuous, and rounded to conform to the hand surface they are adapted to engage. However, one or more of these regions may be stippled, dimpled, ribbed, perforated, or otherwise textured, such as to provide breathability and comfort over prolonged use. Also, as noted above, some or all of these regions may be fabricated from, or coated with, various materials suitable for handgrips, such as soft, resilient elastomers, and so forth. Optionally, such materials may possess a desired amount of “stickiness,” or tack, such as to reduce the amount of finger pressure needed to stabilize the holder in the user's hand.
The illustrated handgrip configuration may provide additional stabilization of the holder in a user's hand 20 when held with the forefinger and thumb, such as by allowing one or more of the user's fingers to urge the second hand rest area into the user's palm and against the user's palmar saddle area 34. Stabilization may be useful in embodiments in which the combined center of gravity of the holder and a hand tool held thereby is not centered directly above the first hand rest area, or is variable. For example, although not required to all embodiments, holder 100 is laterally symmetrical.
If a paintbrush or other tool supported in the holder is also laterally symmetrical, then the combined center of gravity of the holder and the tool gill be located along the holder's plane of symmetry, but still may be forward or rearward of the first hand rest area, considering that paintbrushes and other hand tools may have varying weights and weight distributions. Further, if the tool itself is designed to bear a load, such as the head of a paintbrush, which may carry paint or another substance to be applied to a surface, the center of gravity may change during use of the tool. As such, the handgrip configuration may allow a user to account for such variables by maintaining slight pressure against the grip area pith one or more fingers.
Optionally, as described in greater detail below, some embodiments may include a counterweight device configured to move, the fulcrum of the holder and its load, that is, to transfer the center of gravity of the holder and the hand tool supported thereby, when the holder is held, toward the first hand rest area. For example,
Like a counterweight device, a handgrip configuration is not required to all embodiments. For example, an ergonomic tool holder may include a strap configured to secure a user's hand to the tool holder as an alternative to a handgrip. In some examples, the ergonomic hand tool includes both a hand grip and a strap. The strap may be made of non-resilient materials, such as fabric, cord, or plastic, or made from resilient materials such as rubber or elastic. The strap serves to redistribute a significant portion of the weight of the holder and tool combination to the larger muscles of a user's arm as opposed to the user's hand muscles. In some examples, the strap can support the entire weight of the holder and tool combination.
In some examples, the effective length of the strap is adjustable. The effective length of the strap corresponds to the length of the portion of the strap available to receive and secure the user's hand. The effective length of the strap may be adjusted with buckles, buttons, cleats, and/or hook-and-loop fasteners in known manners. Adjusting the effective length of the strap enables the tool to accommodate larger and smaller hands and to facilitate user comfort by increasing or decreasing how tightly the strap secures the user's hand.
As a further example of an ergonomic tool holder that does not include a handgrip of the form described above.
Similar to holder 100, body 202 of holder 200 includes forefinger and thumb rest areas 206 respectively defined by outwardly-facing surfaces 208 of opposing side regions of the body 202, a first hand rest area 210 defined by a bottom-facing surface 212 of the body 202 disposed rearward of the forefinger and thumb rest areas 206, and a second hand rest area 214 defined by a rearward-facing surface 216 of the brace portion 204. Holder 200 is also held in a similar manner in a user's hand, with the user's forefinger and thumb engaging the forefinger and thumb rest areas 206; when so held, the first and second hand rest areas 210, 214 respectively engage the dorsal saddle area and the palmar saddle area of the user's hand. Additionally, a continuous intermediate surface 218 extending between the first and second hand rest areas 210, 214 engages the region between thumb and forefinger of the user's hand, when the holder 200 is so held.
Also similar to holder 100, body 202 of holder 200 supports paintbrush 10 by means of a tool support portion 230, which is shown to be adapted to hold a portion of paintbrush 10 therein, with the working end thereof, e.g., the paintbrush head 16, oriented forward from a forward end region of the body 202. Although not specifically illustrated, the tool support portion 230 of holder 200 is configured somewhat similarly to that of holder 100, in that it includes a channel disposed between, and defined by, a pair of parallel walls having interior surfaces adapted to retain a portion of the paintbrush.
Because the body 202 of holder 200 is abbreviated in size as compared with that of holder 100, it may be configured to engage the paintbrush (or other hand tool) closer to the center of gravity of the hand tool. Thus, as shown, the tool support portion 230 of holder 200 is shown to engage more of the neck 14 and the ferrule 18 of paintbrush 10, rather than its handle 12 as compared with tool support portion 104 of holder 100. Additionally, tool support portion 230 is shown to include retaining means in the form of a pair of magnets 232 positioned to attract the metallic ferrule 18 of the paintbrush held therein.
Holder 200 is also shown to include a counterweight device 250 configured similarly to that of holder 100; that is, counterweight device 250 is in the form of a selectively attachable clip 252 mounted on the end of handle 12 of the paintbrush. Clip 252 carries weights 254, which, as explained below, may be interchangeable with heavier or lighter weights.
The relatively abbreviated size and minimized design of holder 200 may offer advantages over the configuration of holder 100, such as in manufacturing, by requiring less material and/or fewer fabrication steps. For example, the construction of holder 200 may be unitary, such as being formed from a single piece of material such as an elastomer or other flexible material.
Holder 200 may be customized for use with a paintbrush of a particular gauge, size, weight, configuration, and so forth; for example, holder 200 may be fabricated for a particular paintbrush type having known dimensions and a known center of gravity, such that the holder may be shaped to receive the paintbrush and weighted so that the combined weight of the paintbrush and the holder (with, or without, a counterweight device such as 250) is centered above the first hand rest area 210. Holder 200 optionally may be adapted to be permanently coupled to a paintbrush, for example by the inclusion of adhesive surfaces in the tool support portion configured to bond with the portion of the paintbrush received therein.
In general, the larger a user's hand, the greater the thickness of the saddle of the user's hand. Of course, different hand proportions may result in a thicker or thinner saddle area even among individuals having the same hand size. In some embodiments, the ergonomic hand tool holder may accommodate different hand sizes and proportions, such as by being adapted to conform to saddle areas of different dimensions. For example, such as with the configuration shown in holder 200, the material from which the holder is fabricated may itself be flexible enough to allow the holder to conform to different hand sizes. However, other embodiments, such as embodiments similar to the holder shown at 100, may include one or more articulating components, for example a handgrip that is configured to articulate, such as to adjust the angle and/or distance between the first and second hand rest areas. Such a feature may allow users having different hand sizes to find a comfortable “saddle fit” for their hands, or may simply allow a user to choose to make the fit of the holder looser or more snug, by adjusting the articulating component(s).
Although not specifically shown, holder 300 includes a tool support portion generally indicated at 314 disposed between opposing side regions of the body 302 and configured to receive and hold at least a portion of a hand tool therein. Tool support portion 314 may be substantially similar (or identical) to tool support portion 106 of holder 100, in that it includes a channel defined by a parallel pair of longitudinal walls 316 and a channel floor 318. As noted above, however, the precise configuration of tool support portion and an optional retaining means incorporated therein may be varied from those shown and described herein without departing from the concepts encompassed by this disclosure.
Also although not shown in this view, holder 300 includes forefinger and thumb rest areas disposed on outwardly-facing surfaces of the opposing side regions of the body 302, such that the holder may be held as described above, engaging the saddle area of a user's hand when held.
In the view shown in
The handgrip 304 of holder 300 articulates to adjust the angle A between the first and second hand rest areas. The handgrip may be thought of as including a proximal section 330 a distal section 332, such that the distal section is configured to articulate with the proximal section. As become clear from the following description, however, the articulating mechanism may be disposed at any point along the handgrip, such as at the joint between the handgrip and the body, such that the handgrip may be described to articulate with the body, irrespective of the proximal and distal sections of the handgrip.
The articulation of handgrip 304 is accomplished by means of a hinge 334 formed by a section of wall 324 located on the rear of handgrip 304 that connects the proximal and distal portions, which are otherwise separate from each other (e.g., on the opposing sides and the forward sides of the handgrip). A V-spring 336 sits in the section 338 intermediate the proximal and distal sections, biasing the forward edges of said sections away from each other, and an adjustment screw is threaded through the ends of the V-spring and secured on either end to portions of the wall 322 forming the proximal and distal sections. From this configuration, it is clear that adjustment of angle A may be accomplished by turning the adjustment screw in either direction, such as by means of a screwdriver (not shown) inserted through an opening 342 in channel floor 318, which correspondingly adjusts the distance between the forward edges of the proximal and distal sections, allowing the distance between the first an second hand rest areas to be changed.
The adjustment screw 340 thus also operates to lock the handgrip in a selected position. The limits and relative ease of adjustment, in this configuration, may be a function of the length of the adjustment screw, the resiliency of the material chosen for the wall 322 of the case 320, the resiliency of the V-spring, and so forth. Typically, the intermediate section is formed of (or filled with) a compressible and resilient material such as a thermoplastic polyurethane (“TPU”) or similar elastomer, for example to provide mechanical stability to the configuration and relieve stress on the portion of wall 322 that forms the hinge 334.
Also, although not required to all embodiments,
The articulation enabled by the handgrip configuration shown in
Handgrip 404 is shown to include a proximal section 410, a distal section 412, and an intermediate section 414 disposed therebetween. A connecting strut 416 extends between and connects the proximal and distal sections, with an end anchored in each section, which are shown to be substantially solid in construction and are formed of a suitably rigid material, as noted above. Intermediate section 414 is formed of a compressible, resilient, and comparatively more flexible material, such as TPU or a similar suitable elastomer, and also formed of a number of stacked ribs.
The connecting strut is fabricated from a malleable material such as aluminum or a suitable metal alloy, and, owing to the flexibility of the intermediate section, is bendable therein. Accordingly, the articulation of handgrip 404 is achieved simply by bending the portion of the strut 414 housed within the intermediate section, to adjust the angle A between the first and second hand refit areas. The strut may be formed to limit the bending thereof to within only one plane, such as the vertical plane of symmetry of the holder, such as by conventional means; alternatively, bending may be limited by the geometry of the intermediate section, such as by providing spacing between adjacent ribs on the forward and rear sides of the handgrip, but not on opposing sides, and so forth. Similar techniques may also function to retain the handgrip in a desired position after adjustment.
As noted above, other articulation means are possible, including a ball and socket mechanism, a gear mechanism, variations of the illustrated spring-biased adjustable screw and bendable connecting strut configurations, and so forth. Independent of the actual configuration employed, adjusting the angle and/or distance between the first and second hand rest areas of a holder by means of an articulating handle allows the holder to be adjustable to a user's hand size or proportion and/or to a desired fit. Not only may such adjustability be favorable from the standpoint of user comfort when holding the holder, but providing a snug fit against the saddle area of a user's hand may increase user control and ease of manipulation of the tool held in the holder, and correspondingly reduce the need for exerting finger pressure on the handgrip, factors that contribute to reducing user fatigue and the possibility of stress injuries.
As noted above, the ergonomic tool holders disclosed herein are designed to distribute the combined weight of the holder and the tool supported thereby to the dorsal saddle area 36 of a user's hand 20. As such, the first hand rest area of the holders disclosed herein is generally configured to be broad in width and length, such as to encompass a large region of the dorsal saddle area. User fatigue is reduced when the center of gravity of the combined load is located above the first hand rest area, because the weight is borne by the user's arm, and fewer muscles of the user's fingers, wrist, and hand are needed to balance the holder. To this end, the ergonomic tool holders may include a counterweight device (150, 250) such as shown in
Device 150 is shown in greater detail in
As noted above, counterweight devices 150, 250 are shown as separate components from holders 100 and 200, but some holder embodiments may include one or more connected counterweight devices. For example, a clip such as clip 152 or 252 may be connected to the body of a holder by means of a tether, allowing a user the option of connecting the clip to the tool used with the holder. Other holder embodiments may incorporate or integrate one or more counterweight devices.
For example, a fifth example embodiment of an ergonomic tool holder, shown at 500 in
Holder 500 also includes a tool support portion 520 adapted to support at least a portion of a hand tool with the working end thereof oriented generally forward from a forward end region of the body. More specifically, in this embodiment, tool support portion is disposed on the forward end region of the body and is in the form of a mounting base 522 that is configured to detachably receive the head 16 of a paintbrush 10, or any such interchangeable tool portion provided with corresponding structure to mate with base 522.
Holder 500 is also shown to include a handle 530 extending rearward from the rear end of the body 502, and is oriented slightly upward to provide clearance for the forearm (not shown) of a user holding the holder 500. In this embodiment, the handle 530 can be thought of as having at least two functions. First, the handle may provide a built-in reach extension for the paintbrush head or other tool portion mounted to the tool support portion 520. Second, the cantilevered weight of the handle functions as an integrated counterweight device for the combined load of the holder and the tool portion supported thereby, to locate the center of gravity of the load over, or at least move it toward, the first hand rest area. Toward this end, the handle 530 is provided with a chamber 532 adapted to accept one or more removable weights, indicated generally at 534. The weight or weights may take desired form, such as shaped to fit completely within the chamber 532, as shown, or may be larger, and provided with mating structure adapted to be received within chamber 552.
It is obvious from the foregoing description of the various inventive concepts disclosed herein, and the example implementations thereof in the several illustrative embodiments shown in the drawings, that many variations may be made to the ergonomic tool holders of the present invention without departing from the scope thereof. For example, holders may be adapted to support hand tools of many different shapes, sizes, and configurations, for example by incorporating a suitable tool support portion. Moreover, the holders described herein may be adapted for use with, or incorporated in, designs for power tools, such as drills, paint sprayers, and so forth. Furthermore, the various features shown in the several illustrative embodiments may be incorporated, or not incorporated, in still other embodiments consistent with this disclosure.
Thus, although the present invention has been shown and described with reference to the foregoing operational principles and illustrated examples and embodiments, it will be apparent to those skilled in the art that various changes in loan and detail may be made without departing from the spirit and scope of the invention. The present invention is intended to embrace all such alternatives, modifications and variances that fall within the scope of the appended claims.
This application claims the benefit of U.S. Provisional Application No. 61/573,572, filed on Sep. 8, 2011 the entire disclosure of which is incorporated herein by reference for all purposes.
Number | Date | Country | |
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61573572 | Sep 2011 | US |