WO2007009075A2

WO2007009075A2 - Foldable ergonomic hand tool

Info

Publication number: WO2007009075A2
Application number: PCT/US2006/027414
Authority: WO
Inventors: Daniel P. Hurt
Original assignee: Legacy Holdings, Inc.
Priority date: 2005-07-13
Filing date: 2006-07-13
Publication date: 2007-01-18
Also published as: WO2007009075A3

Abstract

The present invention provides a hand tool for providing ergonomic support via a brace structure that is pivotally connected to a first end of an intermediately-disposed handle. A stem extends between and couples a working element of the tool to a second opposed end of the intermediate handle. The hand tool is thereby modifiable in its operating and storage configurations to most efficiently meet the needs of the user.

Description

441612666 US

FOLDABLE ERGONOMIC HAND TOOL Field of the Invention The present invention relates to hand tools generally, and more particularly to a hand tool having an ergonomic design that increases the fulcrum length achieved when utilized by a user relative to conventional hand tools. The ergonomic hand tool of the present invention is customizable by a user to minimize stress placed on a user' s wrist during operation of the tool.

Background of the Invention

Hand tools, such as those commonly utilized in garden or yard applications, have been embodied in a wide variety of configurations. Typically, however, such hand tools comprise a frame having a working element disposed at- one end of the frame and a handle, generally axially aligned with the elongate direction of the working element, disposed at the opposing end of the frame. Through such a configuration, a significant portion of the resistive forces encountered in the operation of the hand tool are focused at the user's wrist. Therefore, a relatively large amount of force must be applied at the user' s wrist in order to properly operate the hand tool. The application of such forces at the user's wrist can result in early fatigue, soreness, and even medical problems, such as carpal tunnel syndrome.

Recent hand tool designs have attempted to address the problems stated above by incorporating a handle that is disposed intermediate a working element end of the associated frame and an opposite, proximal, end of the frame, with the proximal end of the frame being adapted to be operably placed above the forearm of the user while the user grasps the intermediately-disposed handle. In such a manner, operating forces focused at the user's wrist are substantially eliminated, with such forces being redirected to the user's forearm. Moreover, since the length of the fulcrum developed in such modified tools is the distance from the user' s elbow to the working element, as compared to being from the user's wrist to the working element of the tool, the magnitude of leverage available to the user is greatly enhanced. The increase in leverage achieved in the modified intermediate- handle designs correspondingly substantially reduces the magnitude of resistive forces placed upon the user's elbow. As a result, fatigue, soreness, and medical problems associated with operating hand tools is substantially diminished.

Examples of hand tools incorporating such a modified design are illustrated in U.S. Patent Nos-. 5,813,206 and 5,937,627 issued to McKitrick. While the devices described in the above-cited patents provide useful operational characteristics, the fixed nature of the intermediate handle of such devices renders the tools somewhat difficult to store, display, and ship. In addition, the fixed handle configurations described in the cited patents do not provide for a convenient means of replacing the handle with a customized and/or replacement handle.

U.S. Patent Appln. No. 10/786,767 filed on February 25, 2004, herein incorporated by reference, improves upon the above devices by incorporating a pivotable handle. The pivotable handle in the above-cited patent application has a first end that is pivotally connectable to the frame of the hand tool, whereas the second, opposing, end of the handle extends freely from the frame. ^he handle, however, provides only a single operational position and a single storage position. As such, the user is unable to modify the relative orientation of the handle into a desired one of a plurality of operating positions most convenient and comfortable to the user.

It is therefore a principal object of the present invention to provide a hand tool that is selectively configurable to the individual preferences of a user.

It is a further object of the present invention to provide a hand tool having a handle that is pivotally connected to a proximal end portion of the hand tool.

It is yet another object of the present invention to provide a hand tool having an intermediate handle portion that is integrally formed with a distal portion of the tool, with the working element being interchangeable with other working elements at a distal end of the tool.

It is still a further object of the present invention to provide a hand tool that is convenient to store and display upon retail shelves and/or in small storage spaces.

Summary of the Invention

The present invention provides a hand tool having a working implement that may be removably connected to a central structure. The working element may be any of a variety of implements such as a spade, tined element, and the like. The implement is coupled to a stem, which, in turn, is connected to a first end of a handle. Preferably, the stem extends from the handle in a substantially transverse orientation with respect to a longitudinal axis of the handle. The handle has a second end, opposite the first end, that is pivotally connected to a brace structure. The brace structure includes individual members that extend from the handle. A bracing element extends between the individual members for^'operably bracing against a user's forearm.

The stem may include a telescoping capability, wherein • a first elongate structure is configured to allow a second elongate structure to be slidably positioned within a lumen of the first elongate structure. The working element may also be interchangeably connected to the distal end of the stem allowing a user to interchange different functional working elements in accordance with the purpose of use of the hand tool.

These and additional advantages and features of the^* present invention are described in more detail in the following sections.

Brief Description of the Drawings

Fig. 1 is a perspective view of a hand tool in accordance with the present invention.

Fig. IA is a magnified view of a portion of the hand tool illustrated in Fig. 1. Fig. IB is a magnified view of a portion of the hand tool illustrated in Fig. 1.

Fig. 1C is a magnified view of a portion of the hand tool illustrated in Fig. 1.

Fig. 2 is a perspective view of the hand tool illustrated Fig. 1.

Fig. 3 is a perspective view of a hand tool in accordance with the present invention.

Fig. 3A is a detailed view of a portion of the hand tool illustrated in Fig. 3. Fig. 4 is a perspective view of a hand tool in accordance with the present invention. ^■ Fig. 5 is a perspective view, of a hand tool in accordance with the present invention.

Fig. 6" is a perspective view of the hand tool illustrated in Fig. 5 in a folded orientation.

Fig. 7 is a perspective view of a quick connection mechanism in accordance with the present invention.

Fig. 7A is an illustration of quick connection mechanism in accordance with the present invention.

Detailed Description of the Preferred Embodiments The objects and advantages enumerated above together with other objects, features, and advances represented by the present invention will now be presented in terms of detailed embodiments described with reference to the attached drawing figures which are intended to be representative of various possible configurations of the invention. Other embodiments and aspects of the invention are recognized as being within the grasp of those having ordinary skill in the art.

A first embodiment of an ergonomically designed hand tool in accordance with the present invention is illustrated in Figs. 1 and 2. Fig. 1 shows the hand tool 10 in a first, working configuration 40, and Fig. 2 shows the hand tool 10 in a second, storage configuration 42.

The hand tool 10 of the current embodiment includes, generally, an elongate stem 30 having a first end 32 and an opposing, second end 36. Handle apparatus 19 is preferably pivotally coupled to first end 32 of stem 30, while a working element 50 (shown as a claw in Figure 1) is secured to second end 36 thereof. In preferred embodiments, working element 50 is removably secured to second end 36 of stem 30. In use, handle apparatus 19 provides support and minimizes ^'the stresses delivered to a user's wrist by transferring inertial forces developed at the interface between the working surface and working element 50 to the user's forearm. As such, the inertial forces are focused at a fixed body structure (forearm) instead of a movable body structure (wrist) that must be held in place by muscle, ligaments, and tendons. The focusing of the inertial forces at the user's forearm correspondingly reduces the user's stress and fatigue by minimizing the use of muscles to maintain tool 10 in a proper working orientation. In addition, handle apparatus 19 minimizes the effort necessary to operate tool 10, such as in pulling working element 50 through the ground, by lengthening the fulcrum, as measured between the working element and the focal point of movement in the user's body. In particular, the focal point of movement for the user of tool 10 of the present invention is the elbow, while the focal point of movement for users of conventional hand tools is the wrist. Such a distinction substantially increases the working fulcrum length, thereby significantly decreasing the torque necessary to operate tool 10.

Handle apparatus 19 includes a handle 20 having a first, upper end 22 that is pivotally connected to the stem 30 such that it is selectively lockable in one of a plurality of orientations with respect to stem 30. As shown in Figure 1, handle 20 is preferably lockable in at least a first operating orientation in which handle 20 is substantially perpendicularly disposed with respect to stem 30.

Fig. IA provides a detailed view of the pivotable connection between the first end 22 of the handle 20 and the first end 32 of the stem 30. In one embodiment, a pivot pin 34 extends through tab 23 of handle 20 and the first end 32 of the stem 30 so as to protrude outwardly from stem 30. The protruding portions of pivot pin 34 act as respective pivot axes about which tab 23 of handle 20 may operably pivot. In other embodiments, however, two or more distinct pivot pins may extend^" outwardly from stem 30 so as to provide for distinct loci for pivoting motion of handle 20 with respect to stem 30. Tab 23 of handle 20 has one or more pivot pin receptacles 26 for receiving and pivoting about each of the pivot pins 34 extending from opposing sides of the stem 30. Tab 23 of handle 20 preferably further includes a button receptacle 27 for selectively receiving a recessible button 35 that extends from first end 32 of step 30.

When the handle 20 is pivoted to the working configuration 40, the button 35 maintains the orientation of the handle 20 with respect to the stem 30 by extensively protruding into button receptacle 27 of tab 23. The button 35 may alternatively be depressed out from engagement with receptacle 27 to allow the handle 20 to freely pivot with respect to the stem 30. Although pivot pin 34 and button 35 and corresponding receptacles 27 are illustrated in the present embodiment, any suitable pivotable connection mechanism may be utilized in conjunction with the present invention for selectively locking a pivot joint.

Handle apparatus 19 further includes a brace structure 80 that is coupled to second end 24 of handle 20. In preferred embodiments, brace structure 80 is pivotally coupled to second end 24 of handle 20, such that brace structure 80 may be selectively pivoted and locked in any one of a plurality of positions with respect to handle 20.

As illustrated in Figure 1, brace structure 80 includes a support frame 84 having two spaced apart and substantially parallely disposed elongate members which originate from second end 24 of handle 20, and preferably from respective opposing side portions 21 thereof,- Receiving portions 25 are provided in second end 24 of handle 20 as apertures for operably receiving respective ends 82 of the elongate members 86. In preferred embodiments, elongate members 86 are pivotally coupled to handle 20 within respective receiving portions 25. The engagement of ends 82 of elongate members 86 within receiving portions 25 is preferably accomplished through a friction fit, such that brace structure 80 may be pivoted with respect to handle 20 through a plurality of distinct relative orientations. In other embodiments, however, the connection of elongate members 86 within receiving portions 25 provides for multiple distinct orientations of brace structure 80 with respect to handle 20 through, for example, engaging surface features of ends 82 of elongate members 86 and respective receiving portions 25 of handle 20.

The brace member 88 is operably coupled to the pair of elongate members 86 at a distal, second end -83 of the brace structure 80. The brace member 88 defines a flexible curved surface that extends between the elongate members 86 so as to operably engage with a forearm of the user.

Brace member 88 is preferably fabricated from a resilient or elastic material which deforms a certain degree under stress. Such a resilient characteristic for a brace member 88 is incorporated for comfort purposes to the user, particularly in that resistive forces generated in the operation of the hand tool 10 tend to force the brace member 88 down upon the forearm of the user. With the brace member 88 being fabricated of a relatively soft resilient material, such as synthetic rubber material, the user is spared from encountering a rigid structure bearing against their upper forearm. In other embodiments of the, present invention, however, brace structure 80 may instead include a single elongate member 86 originating at handle 20 that diverges into a pair of elongate members 86 at a position spaced from the handle 20. As a further feature of the present invention, an aperture 89 may be provided in the brace member 88 so that the hand tool 10 may be conveniently suspended from a substantially horizontally disposed protrusion such as a nail, hanging hook, shelving pin, or the like. The aperture 89 accordingly accommodates a substantially vertical storage and display orientation for the hand tool 10, which vertical^' orientation is most desired in the marketing industry.

As shown in Fig. IB, the stem 30 may preferably be telescopically extendible through the cooperation of a first, outer sleeve 38 and a second inner sleeve 39. The outer sleeve 38 defines a lumen 37 extending along an axis "a", with the second, inner sleeve 39 being coaxially engageable within the lumen 37.

The total length of the stem 30 may be operably adjusted to a predetermined length by telescopingly positioning the inner sleeve 39 with respect to the outer sleeve 38. The relative positions of inner sleeve 39 and outer sleeve 38 may be selectively locked using a lock mechanism 60 wherein the outer sleeve 38 has a spring-biased, retractable button 62 that selectively extends through an operably aligned one of a series of apertures 64 in the inner sleeve 39. Thus, the inner sleeve 39 may be disengaged from a locked characteristic by depressing the button 62 and sliding the inner sleeve 39 to a new relative position within outer sleeve 38. A spring 69 provides a biasing for the button 62 and lock mechanism 60 in a locked orientation. When the button 62 is depressed, the spring 69 compresses and thus removes the lock mechanism 60 from the corresponding aperture 64 by causing the locking mechanism 6t) to pivot about a fulcrum 67 extending from the outer sleeve 38, allowing the inner sleeve 39 to be slidably adjusted with respect to the outer sleeve 38. Such locking mechanism may include a housing 61 such that only the button 62 is accessible in order to operate the locking mechanism 60.

In the embodiment shown in Figs. 1 and 2, the working element 50 is a claw. The present invention, however, contemplates the use of a variety of configurations for working element 50. Examples of such alternative working elements include, for example, shovel elements, trowel elements, rakes, spades and the like. In working configuration 40 of the present invention, the stem 30 is oriented along axis ^Ma", with such working element 50 encompassing the respective portion of the hand tool 10 that is utilized to engage the earth or other targeted surface.

The embodiment illustrated in Figure 1 further includes the additional feature of a supplemental handle 90. As shown in more detail in Fig. IB, the supplemental handle 90 preferably extends perpendicularly outwardly from stem 30, and in an orthogonal relationship with handle 20 when handle 20 is in a first operating orientation 40. In the present embodiment, the supplemental handle 90 may extend from either or both sides of the stem 30. Additionally, the supplemental handle 90 may be pivotally connected to the stem 30 such that it has a first, operable configuration 40 extending perpendicularly with respect to the stem 30, and a second, storage, configuration 42 substantially parallel and adjacent to the stem 30. As shown in Fig. 1C, the supplemental handle 90 preferably includes a 'locking mechanism 93 that lockingly engages supplemental handle 90 in one or more fixed positions about a pivot axis defined by pivot pin 91. In one embodiment of the invention, a spring-biased, retractable button extends outwardly from supplemental handle 90 in such a manner so as to extensively engage within a corresponding aperture 98 in flange 95 of locking mechanism 93 when supplemental handle 90 is disposed in operating configuration 40. Supplemental handle 90 is therefore pivotally coupled to stem 30 at mounting portion 99, which mounting portion engages about at least a portion of the stem 30, such as by frictional forces. In use, the hand tool 10 has a first, operable, configuration 40 wherein the stem 30 extends along axis "a" [shown in Figure 1] that is transverse and substantially- perpendicular with respect to axis "b" defined by the elongate dimension of the handle 20 as oriented in Figure 1. In operable configuration 40, the brace structure 80 extends substantially along axis V.

As shown in Fig. 2, hand tool 10 has a -second, storage, configuration 42 wherein the handle 20 is pivoted with respect to the stem 30 such that the handle 20 and stem 30 are substantially parallel and adjacent to each other. In addition, brace structure 80 is pivoted with respect to handle 20 so as to be in axial alignment with handle 20 and adjacent to stem 30. The supplemental handle 90 is pivoted to extend substantially parallel to the stem 30 as well. In this configuration, hand tool 10 of the present invention takes up little space for ease of shipping and storage.

Fig. 3 shows an embodiment of the present invention having one or more quick connect mechanisms 70, allowing, for example, the addition of stem extensions 202, 206, and/or to interchangeably connect different working elements 150 thereto . Fig. 3A provides a more detailed view of a suitable quick connect mechanism 70 for use with the present invention. A connecting end 212 of a stem 200, stem extension 202, 204, or working element 150 is received within a receiving lumen 210 of housing 208. The connecting end 212 may have an alignment groove 214 that operably receives a corresponding alignment ridge 216 of housing 208. A releasable locking mechanism 217 includes a button 218 that is connected to a locking arm 220. As shown in Figure 3A, locking arm 220 is configured to selectively engage with a corresponding aperture 222 in the sidewall of the connecting end 212. The connecting end 212 of the respective stem, stem extension, or working element is locked in place when the locking arm 220 engages within the aperture 222. Likewise, connecting end 212 may be unlocked by depressing the button 218, thereby removing the locking arm 220 from the aperture 222. The presently described quick connect mechanism 70 is illustrative only, and any .suitable connecting mechanism may be used in accordance with the present invention.

The extension stems 202, 204 and working element 150 may be alternatively interchanged, or used in combination with one another, as determined by a user.

Fig. 4 shows yet another embodiment of the hand tool of present invention wherein a first handle 300 is shown connected at a first end 301 to the stem 320, such that a second end 302 of the first handle 300 is free. The first handle 300 is preferably pivotally connected to stem 320 such that it may pivot from an operable configuration, as shown, to a storage configuration wherein the first handle 300 is in a position parallel to the stem 320. A second handle 332 is shown extending in a direction perpendicular to the plane defined by the stem 320 and first handle 300 when in operating configuration. The second handle 332 is also pivotally connected to the stem 320 so as to enable pivoting to a storage configuration wherein the second handle 332 is parallel and adjacent to the stem 320. The stem 320 may include telescoping capabilities and quick connect capabilities as discussed with reference to the various embodiments described herein.

A further embodiment of the present invention is shown in Figs. 5 and 6. Hand tool 101 has a handle 100 attached at a first end 104 to a pivotally adjustable brace structure 110, and a second end 102 of the handle 100 being integrally formed with stem 130. The brace structure 110 preferably has a pair of elongate members 112 that are pivotally connected to opposing sides of the handle 100, thereby receiving the handle 100 therebetween. In preferred embodiments, one or more spring-biased retractable buttons 116 are disposed at opposing sides 105, 107 of first end 104 of handle 100. Retractable buttons 116 are preferably positioned at handle 100 so as to selectively engage within corresponding apertures 114 in respective proximal ends of elongate members 112. Preferably, each elongate member 112 includes a plurality of apertures 114 for selectively receiving a locking button 116 therein. In such a manner, brace structure 110 may be lockingly secured at a plurality of pivot positions about respective pivot pins 103. As such, the brace structure 110 can be pivotally adjusted and locked at a plurality of points with respect to the handle 100 by receiving button 116 within a selected one of apertures 114. This mechanism allows a user to selectively adjust the angle of the brace structure 110 with respect to the handle 100, and corresponding to working element 150, to a comfortable configuration based upon personal preference. The brace structure 110 has a brace support 118 that extends between respective distal ends Qf the elongate members 112. The brace support 118 is preferably curved to comfortably accommodate ^' a user's forearm.

The second end 102 of the handle 100 may be integrally formed with the stem 130, or may provide a quick connect mechanism for interchangeability of a stem 130 and/or working element 150. The stem 130 may be locked to the first end 102 of the handle 100 by any suitable means such as threaded connectors, button and aperture connections, or any other such suitable means. The distal end 134 of the stem 130 may, alternatively or in combination, provide a quick connect attachment with the working element 150 to allow a working element 150 to be interchanged with another working element selected from a plurality of different working elements. The connection of the working element 150 to the stem 130 may likewise include a number of variations in mating mechanisms.

As shown in Fig. 6, the hand tool 101 has a storage configuration wherein the brace structure -110 is pivoted towards the working element 150 to minimize space taken up by the hand tool 101. Figs. 7 and 7A illustrate an embodiment of a quick connect mechanism in accordance with the present invention. Quick connect mechanism 400 provides a means for quickly connecting and locking an extension stem 420 and/or for quickly interchanging and locking in a new working element 150. Quick connect mechanism 400 provides alignment guides 430, 432, to properly orient a stem 420 and/or working element 150 therewith. The quick connect mechanism 400 additionally provides a selectively pivotable mechanism 436 to allow a connected stem 420 and/or working element 150 to pivot with respect to a handle or brace structure connected thereto. The quick connect mechanism 400 preferably includes a lock' portion 401 and a cooperating mounting portion 422 of a stem 420 (as shown in more detail in Fig. 7A) or working element 150 (not shown) .

The lock portion 401 has a head 402 that includes an elongate portion 404 defining a lumen 406. At a first end of the head 402 is a connecting portion 408, which axially extends from a threaded outer circumferential portion 410 adjacent to a central body 412 of the quick connect mechanism 400. A stem 420 has a cooperating mounting portion 422 that provides a receptacle 424 that is operably engageable with the head 402. Preferably, the receptacle 424 defines an inner threaded portion 426 that threadably engages with the threaded portion 410 of the lock portion 401 to secure the stem 420 to the lock portion 401.

A pair of grooves 430 in stem 420 operably engage with alignment guides 430, 432 to appropriatel-y arrange, for example, a working element in alignment with stem 420 for efficient function. The body portion 412 of the lock portion 401 additionally provides a set of opposing and inwardly oriented teeth 436. The teeth 436 allow the body portion 412 to be pivoted into selected ones of a plurality of positions by engaging with a corresponding set of interlocking teeth disposed on a correspondingly configured handle. This arrangement allows, for example, the selective pivotable adjustment of a handle (not shown) and stem 420, each being connected to corresponding sections of the body portion 412.

Claims

ClaimsWhat is claimed is:

1. A hand tool comprising: a) a handle having a first end and an opposing second end, said first end and said second end defining an elongate dimension of said handle therebetween; b) a brace structure pivotally coupled to said first end of said handle; and c) a working element coupled to said second end of said handle, said working element extending in a orthogonal direction with respect to said handle.

2. The hand tool according to claim 1 wherein said working element is pivotally connected to said second end of said handle by a stem.

3.. The hand tool according to claim 2 wherein said working element is removably connectable to said stem.

4. The hand tool according to claim 3 wherein said stem includes a first elongate structure and a second elongate structure that is slidably positionable within said first elongate structure.

5. The hand tool according to claim 1 wherein said brace structure includes a pair of elongate members pivotally connected to opposing sides of said first end of said handle.

6. The hand tool according to claim 5 wherein said brace structure includes a brace support extending between said pair of elongate members.

7. The hand tool according to claim 1 wherein said brace structure is selectively positionable with respect to said first end of said handle.

8. The hand tool according to claim 7 wherein said brace structure is pivotably coupled to said first end of said handle.

9. The hand tool according to claim 1 wherein said working element is selectively positionable with respect to said second 'end of said handle.

10. A hand tool comprising: a) a handle having an elongate dimension defined between a first end and an opposing second end; b) a brace support pivotally coupled to said first end of said handle, said brace support configured to selectively lock in a plurality of distinct pivot positions; and c) a working element pivotally coupled to said second end of said handle.

11. A hand tool comprising:

(a) a handle having a length defined between a first end and a second end; (b) a stem extending from said first end of said handle to a working element; and

(c) a brace structure pivotally coupled to said second end of said handle.

12. A hand tool as in Claim 11 wherein said stem is pivotally coupled to said first end of said handle.

13. A hand tool as in Claim 11 wherein said stem integrally and substantially perpendicularly extends from said first end of said handle.

14. A hand tool as in Claim 11 wherein said working element is removably securable to said stem.

15. A hand tool as in Claim 11 wherein said stem is selectively extensible along a longitudinal axis thereof.

16. A hand tool as in Claim 11 wherein said brace structure is configured to operably brace against an upper side of a user' s forearm while the user operably grasps said handle .

17. A hand tool as in Claim 11 wherein said brace structure includes two distinct brace members diverging from said handle into a spaced apart and substantially parallel disposition .

18. A hand tool as in Claim 17, including a bracing element extending between said brace members.

19. A hand tool as in Claim 18 wherein said bracing element is fabricated from a resilient material.

20. A hand tool as in Claim 11 wherein said brace structure pivots about a first axis that is substantially perpendicular to a second axis defined by said length of said handle .

■21. A hand tool as in Claim 20 wherein said brace structure is lockably positionable in selected ones of a plurality of pivot positions about said first axis.