EP0940225A2 - Open end ratchet wrench - Google Patents

Open end ratchet wrench Download PDF

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Publication number
EP0940225A2
EP0940225A2 EP19990301595 EP99301595A EP0940225A2 EP 0940225 A2 EP0940225 A2 EP 0940225A2 EP 19990301595 EP19990301595 EP 19990301595 EP 99301595 A EP99301595 A EP 99301595A EP 0940225 A2 EP0940225 A2 EP 0940225A2
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EP
European Patent Office
Prior art keywords
distal
wrench
slot
plate
plates
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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EP19990301595
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German (de)
French (fr)
Inventor
John L. Stanton
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John L. Stanton
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Priority to US36349 priority Critical
Priority to US09/036,349 priority patent/US6223630B1/en
Priority to US11462898A priority
Priority to US25105099A priority
Priority to US114628 priority
Application filed by John L. Stanton filed Critical John L. Stanton
Publication of EP0940225A2 publication Critical patent/EP0940225A2/en
Withdrawn legal-status Critical Current

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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B25HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25BTOOLS OR BENCH DEVICES NOT OTHERWISE PROVIDED FOR, FOR FASTENING, CONNECTING, DISENGAGING OR HOLDING
    • B25B13/00Spanners; Wrenches
    • B25B13/46Spanners; Wrenches of the ratchet type, for providing a free return stroke of the handle
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B25HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25BTOOLS OR BENCH DEVICES NOT OTHERWISE PROVIDED FOR, FOR FASTENING, CONNECTING, DISENGAGING OR HOLDING
    • B25B13/00Spanners; Wrenches
    • B25B13/02Spanners; Wrenches with rigid jaws
    • B25B13/08Spanners; Wrenches with rigid jaws of open jaw type

Abstract

A wrench has a pair of jaws spaced to define an opening for a workpiece. A pair of plates, are mounted on the jaws for selective movement between first and second positions. In the first position, the plates are substantially immobile with respect to each other. In the second position, a first one of the plates is pivotable with respect to a second one of the plates. Thus, the wrench tightens (or loosens) the workpiece when rotated in the first direction, and slips over the workpiece in a "ratcheting" manner when rotated in the second, opposite direction.

Description

    Cross-Reference to Related Applications
  • This application is a continuation-in-part of my copending patent application entitled "Open End Ratchet Wrench," Serial No. 09/114,628, filed on July 13, 1998, which is a continuation-in-part of application Serial No. 09/036,349, filed on March 6, 1998, both of which are hereby incorporated herein by reference.
  • Background
  • This invention relates to ratchet wrenches, and more particularly to open-end ratchet wrenches that can be placed on a workpiece from the side.
  • There are many occasions when it is desirable to apply torque to a workpiece (such as nuts, bolts, and in-line hydraulic fittings) in order to, for example, rotate the workpiece with respect to a threaded member. Two well known tools for rotating workpieces are ratchet wrenches and open-end crescent wrenches. Ratchet wrenches are typically close-ended devices that completely encircle the workpiece and are thus installed on the workpiece from the top (or bottom, depending upon the orientation of the workpiece). By contrast, open-end wrenches can be installed from the side of the workpiece.
  • Open-end wrenches are particularly useful in small spaces where there may only be sufficient room to install the wrench from the side. Moreover, in confined spaces, there is often insufficient space to accommodate the ratchet mechanism of typical close-ended ratchet wrenches. In addition, open-end wrenches are a must for tightening/ loosening in-line fittings of hydraulic or fuel lines, which can only receive a wrench from the side.
  • Typical open-end crescent wrenches lack a ratchet mechanism. As a result, during a tightening or loosening operation, the wrench must be removed from the workpiece after it has rotated the workpiece a relatively small amount (such as 30 degrees), and then replaced thereon at a different angle for continued rotation. This procedure is repeated (often many times) until the workpiece is completely tightened or loosened.
  • Open-end ratchet wrenches that resemble typical crescent wrenches have been developed for confined and in-line fitting applications. Some open-end ratchet wrenches employ numerous spring-loaded rollers, cams, or pawls for engaging the workpiece; others use an insert shaped to fit over the workpiece and engage an internal ratchet mechanism. Some of these wrenches encircle the workpiece to such an extent that, even though the wrenches have open ends, they must actually be installed vertically from above or below the workpiece.
  • Another open-end ratchet wrench, described in my U.S. Patent No. 5,456,143, includes a pair of elongated plates that are pivotally mounted to a pair of spaced jaws on the wrench handle. A spring mounted on the handle engages the plates and biases them toward each other so that the plates grasp and turn the workpiece when the handle is rotated in a driving direction. The spring bias is overcome when the handle is turned in the opposite direction, allowing both plates to pivot on the jaws and slide over the faces of the workpiece in a ratcheting manner. Summary
  • This invention features, in a general aspect, a wrench having a pair of jaws disposed on a handle and spaced to define an opening for a workpiece, and a pair of plates each of which includes a workpiece engaging surface adjacent the opening; the plates are mounted on the jaws for selective movement between: a) a first position in which the plates are substantially immobile with respect to each other so that rotation of the handle in a first direction causes the plates to grasp the workpiece between the engaging surfaces and turn the workpiece in the first direction, and b) and a second position in which a first one of the plates is pivotable with respect to a second one of the plates so that rotation of the handle in a second, opposite direction causes pivoting of the first plate and allows the engaging surfaces to slide over the workpiece, thereby allowing the workpiece to remain stationary. Thus, the wrench tightens (or loosens) the workpiece when rotated in the first direction, and slips over the workpiece in a "ratcheting" manner when rotated in the second, opposite direction.
  • The invention unites features of an open end wrench and a ratchet wrench in a wrench that is rugged and simple to make. The wrench has a minimal number of moving parts and thus is much easier to manufacture (and repair) than wrenches which use many individual pawls or rollers to provide ratcheting. In preferred embodiments, the plates each engage the workpiece over a relatively large surface area, thereby maximizing torque transmission and minimizing contact stresses imposed on the wrench and the workpiece. This reduces the risk of damage to the wrench and the workpiece.
  • The spacing between the jaws and the configuration of the elongated plates permit the plates to operate the workpiece while engaging only four faces of the workpiece and encircling the workpiece through an arc of only 240 degrees. As a result, the wrench can easily be inserted onto and removed from the workpiece from the side for ease of use in cramped spaces. In preferred embodiments, the ratcheting operation is assisted by a spring which biases one of the plates toward the opening, which makes turning the workpiece fast and easy while requiring no clearance behind the workpiece.
  • Preferred embodiments may include one or more of the following additional features.
  • The plates are mounted for the selective movement in response to rotation of the handle. No separate locking or unlocking mechanism is needed to change the operating state of the wrench. For example, after turning the workpiece in the first direction, the wrench is simply rotated in the opposite direction to move the plates to the second position for ratcheting.
  • The first plate is mounted to a first one of the jaws so that the distal end of the plate is substantially immobile in the first position, and is pivotable with respect to the second plate in the second position. In one embodiment, only the first plate pivots, and it moves away from the opening and the second plate. In another embodiment, both plates pivot away from the opening and each other.
  • The plates are substantially immobile with respect to each other in the first position in that they cannot spread apart from each other. To further avoid slippage when driving the workpiece, in one embodiment one or both of the plates are mounted so that when in the first position the distal ends of the plates are movable toward each other. This enhances the gripping strength of the plates against the workpiece, and is particularly useful for driving an undersized workpiece.
  • A distal pin on the distal end of the first plate is received by a slot disposed in a distal region of the first jaw. Alternatively, the distal slot is in the first jaw, and the distal pin is on the plate. In each case, the distal pin is disposed in a first portion of the distal slot when the plate is in the first position, and is disposed in a second portion of the distal slot when the plate is in the second position.
  • The first portion of the distal slot is oriented so that the engagement of the distal pin therein holds the distal end of the first plate substantially immobile with respect to the second plate when the wrench is rotated in the first direction, and the second portion of the distal slot is oriented to allow the distal end of the first plate to pivot with respect to the second plate when the wrench is rotated in the second direction. In one embodiment, the distal slot is "V" shaped; that is, the distal slot has a pair of acutely-angled lobes. The base of the "V" is oriented either toward or away from the handle.
  • A proximal pin on the proximal end of the first plate is received by a slot disposed in a proximal region of the first jaw. The proximal slot and the first portion of the distal slot are oriented (preferably along a common arc of curvature) to allow the selective movement of the first plate between the first and second positions. The center of the common arc of curvature is disposed in the opening. The second portion of the distal slot is arranged transversely to the arc of curvature.
  • The proximal pin is also mounted to the proximal end of the second plate. A distal pin at a distal end of the second plate is received by a slot disposed in a distal region of the second jaw. This distal slot is, with the proximal slot, oriented to allow the selective movement of the second plate between the first and second positions.
  • The plates and the spring are arranged so that turning the wrench over with respect to the workpiece reverses operation of the wrench in the first and second directions. That is, with the wrench turned over, the wrench tightens or loosens the workpiece when rotated in the second direction, and produces the ratcheting action when rotated in the first direction.
  • As an alternative to the dual-lobe approach, the distal slot associated with the first plate is oriented transversely to an arc of curvature centered in the opening, with a first portion of the distal slot intersecting the arc and a second portion of the distal slot being positioned radially inside of the arc. The distal pin is disposed in the first portion of the distal slot in the first position, and is movable into the second portion of the distal slot in the second position to cause the first plate to pivot with respect to the second plate.
  • One of the advantages of this embodiment of the wrench is additional manufacturing simplicity. The transverse distal slot is easier to lay out and cut than, e.g., the dual-lobe (e.g., V-shaped) slots of the above-discussed embodiments, and may be more resistant to wear over the long term.
  • The first and second portions of the distal slot are at opposite (distal and proximal) ends of the distal slot. The first and second portions of the distal slot may be curved or straight.
  • The distal slot may also include a region oriented to receive the distal pin and cause the first plate to move toward the second plate and further grip the workpiece when the handle is rotated in the first direction. This region of the distal slot is positioned radially outside of the arc. In one embodiment, the first portion and the region are at a distal end of the distal slot, and the second portion is at a proximal end of the distal slot; in another embodiment, the first portion and the region are at a proximal end of the distal slot, and the second portion is at a distal end of the distal slot.
  • A proximal pin on proximal end of the first plate is received by a proximal slot disposed in a proximal region of the first jaw. The proximal pin is disposed in a first portion of the proximal slot in the first position, and is movable into a second portion of the proximal slot in the second position. The first plate pivots about the proximal pin away from the second plate in the second position. The first and second portions of the proximal slot are oriented along the arc.
  • A spring is positioned to bias the first plate to return from the second position toward the first position.
  • The wrench also includes a second distal pin on one of a distal end of the second plate or a distal region of the second jaw, and a second distal slot disposed in the other one of the distal end of the second plate or the distal region of the second jaw. The second distal pin is disposed in a first portion of the second distal slot in the first position, and is movable into a second portion of the second distal slot in the second position. The first and second portions of this distal slot are also at opposite ends of the second distal slot.
  • In one embodiment, the second distal slot is oriented along the arc so that the second plate does not pivot with respect to the first plate as the second distal pin moves from the first portion to the second portion of the second distal slot. In another approach, the second distal slot is oriented transversely to the arc, with the first portion thereof intersecting the arc and the second portion thereof being positioned radially inside of the arc, so that the second plate pivots with respect to the first plate as the second distal pin moves from the first portion to the second portion of the second distal slot.
  • The first and second portions of the second distal slot may be curved or straight. The second portions of the distal slots are located at opposite ends thereof. Each of the distal slots also comprises a region oriented to receive the respective distal pin and cause the first and second plates to move toward each other and further grip the workpiece when the handle is rotated in the first direction. These regions are positioned radially outside of the arc and are located at opposite ends of the respective distal slots. The first and second plates pivots about the proximal pin away from each other in the second position.
  • Although the plates can have different configurations, it may be advantageous in some embodiments to configure the plates to be identical. This significantly simplifies manufacture and, along with the manner in which the plates are movably mounted to the jaws renders the wrench easily scalable in size. Each plate preferably has a plurality of the engaging surfaces, and each surface is elongated so as to engage a face of the workpiece over a major portion of a length of the face. The engaging surfaces are flat. The engaging surfaces are arranged to define an angle therebetween equal to an angle between adjacent faces of the workpiece. In one embodiment, the portion of each plate that includes the workpiece engaging surface has an enlarged thickness relative to another portion of the plate.
  • Other features and advantages of the invention will become apparent from the following detailed description, and from the claims.
  • Drawings
  • Fig. 1 is a top plan view of an open-end ratchet wrench.
  • Fig. 2 is a side view of the wrench of Fig. 1.
  • Fig. 3 shows the wrench of Fig. 1 with the front face plate removed to illustrate a pair of elongated plates that are pivotally mounted on the wrench.
  • Figs. 4 and 5 are plan and side views, respectively, of one of the plates shown in Fig. 2.
  • Fig. 6 illustrates another embodiment of the wrench being used to turn a workpiece in the driving direction (D). Figs. 7 and 8 show the operation of the wrench of Figs. 6 in the non-driving (ratcheting) direction (R).
  • Fig. 9 is a top plan view of another embodiment of an open-end ratchet wrench.
  • Fig. 10 shows the wrench of Fig. 9 with the front face plate removed to illustrate a pair of elongated plates that are pivotally mounted on the wrench.
  • Figs. 11A, 11B and 12A, 12B are plan and side views, respectively, of the plates shown in Fig. 10.
  • Fig. 13 is a cross-sectional view of the head of the wrench of Fig. 9 engaged with a workpiece (W) and placed against a surface (S).
  • Figs. 14A and 14B show an alternative configuration of the elongated plates shown in Fig. 10.
  • Figs. 15A-15C and 16A-16B illustrate another embodiment of the wrench.
  • Figs. 17A-17E are useful in understanding an alternative configuration for one of the movable plates of the wrench.
  • Figs. 18-20C illustrate another embodiment of the wrench.
  • Figs. 21-23C illustrate yet another embodiment of the wrench.
  • Detailed Description
  • The wrenches of this invention are similar to those of my U.S. Patent No. 5,456,143 ("the '143 patent") and my copending U.S. patent application Serial No. 08/728,627 ("the '627 application"), both of which are entitled "Open End Ratchet Wrench" and are incorporated herein by reference. The wrenches of the present invention have many of the advantages of the wrenches of the '143 patent and the '627 application, plus additional advantages that have been discussed or that will become apparent.
  • Referring to Figs. 1-3, open-end ratchet wrench 15 includes a pair of arcuate jaws 16, 17 at the end of an elongated handle 18. Jaw 16 is somewhat larger than jaw 17 and protrudes more markedly from handle 18 than does jaw 17 for purposes to be described. Jaws 16, 17 and handle 18 are defined by a pair of face plates 20, 22 (Fig. 2). A central plate 24 is sandwiched between face plates 20, 22 in handle 18 to provide space in jaws 16, 17 for a pair of elongated plates 26, 28 that are movably mounted to face plates 20, 22 within jaws 16, 17 in a manner described below. Plates 20, 22, 24 are secured together in handle 18 in any suitable way, such as by screws (not shown). The components of wrench 15 are made of tool steel or hardened steel for ruggedness.
  • One of the advantages of wrench 15 is its simple construction. Front and back plates 20, 22 are identical to each other, and elongated plates 26, 28 are also identically constructed. Thus, wrench 15 is easy to manufacture, and can easily be scaled up or down in size (i.e., enlarged or miniaturized with respect to standard-sized open-end wrenches).
  • As best shown in Figs. 1 and 2, face plates 20, 22 extend longitudinally beyond the distal end 25 of central plate 24 to form a generally "C" shaped head 19 in which arcuate jaws 16, 17 are disposed. Jaws 16, 17 are laterally spaced from each other by any suitable amount to partially encircle a central opening 21 for receiving a workpiece (e.g., the head of a bolt, a nut, or an in-line fitting) by no more than 240 degrees. As a result, sufficient spacing S is provided between the tips and workpiece-engaging surfaces of plates 26, 28 to allow wrench 15 to be inserted onto the workpiece from the side rather than from above (or below) the workpiece.
  • Figs. 4 and 5 show elongated plate 26 separately from the remainder of wrench 15. As discussed, plates 26, 28 are identical, and thus plate 28 is not separately shown. Elongated plates 26, 28 are curved (more specifically, reniform, or kidney, shaped) and are slightly thinner than central plate 24 so that they may move easily between face plates 20, 22. The inner concave sides of elongated plates 26, 28 (i.e., the sides of plates 26, 28 that oppose each other) are notched to define a series of cusps 30, each of which is defined by a pair of flat surfaces 30a, 30b. Each plate 26, 28 includes three notches 31 defined by adjacent cusps 30 of the plate, and plates 26, 28 define another, central notch 31 at the junction between the plates. Elongated surfaces 30a, 30b that meet at a notch 31 are oriented at an angle that matches the angle defined by a pair of adjacent faces of the workpiece (which, for a hexagonal bolt head or nut, is 120 degrees).
  • Plates 26, 28 provide a total of sixteen surfaces 30a, 30b and eight cusps 30 arranged over an arc of 240 degrees (Fig. 1). As a result, the arrangement of surfaces 30a, 30n on plates 26, 28 corresponds to a so-called "12-point" design. (That is, if the plates were to be extended to define a 360 degree figure, they would provide twelve cusps 30 or "points," and twenty four surfaces 30a, 30b. The term "12-point" design is commonly used for socket wrenches to describe the number of "points" defined by the socket.)
  • The proximal ends of elongated plates 26, 28 are stepped-down in thickness at a shoulder 29 to define a shelf 29a at the base of each plate 26, 28. Shelves 29a are approximately one-half of the thickness of the remainder of each plate. A pair of round holes 31a, 31b are formed in each plate 26, 28, one (hole 31a) in the distal region of the plate, the other (31b) in shelf 29a. As discussed below, holes 31a, 31b receive pins that also pass through face plates 20, 22 for movably mounting elongated plates 26, 28 in wrench head 19.
  • Because of their identical shape, when plates 26, 28 are mounted within jaws 16, 17 with their elongated surfaces 30a, 30b facing each other, one plate (e.g., plate 26) will be face-up, and the other (plate 28) will be face-down. As a result, shelves 29a of the two plates will overlap with each other, with their holes 31b aligned in registry.
  • When elongated plates 26, 28 are in their rest position (shown by Figs. 1 and 2), their elongated surfaces 30a, 30b extend into central opening 21 by an amount sufficient to engage and grasp the faces of a hexagonal workpiece when holding a hexagonal workpiece in the position shown in Fig. 3 or in a position rotated by 30 degrees from that shown in Fig. 3. Each elongated surface 30a, 30b is configured to engage a face of the workpiece over a major portion (such as at least 54%) of the length of the face. Elongated plates 26, 28 are restrained in their movement and held between face plates 20, 22 by three pins 32, 34, 36 which pass from face plate 20 to face plate 22 through respective slots 42, 44, 46 in face plates 20, 22 and round holes 31 in elongated plates 26, 28. Pins 32, 36 are secured within the distal holes 31a of respective plates 26, 28, while pin 34 is secured within the aligned proximal holes 31b of plates 26, 28. As discussed below, pin 34 is held sufficiently loosely within hole 31b of plate 26 to allow plate 26 to pivot about pin 34 during ratcheting.
  • Slots 42, 44, 46 in face plate 20 are identical to and are aligned in registry with corresponding slots 42, 44, 46 in face plate 22. Slots 42 are located in a distal region of jaw 17, slots 44 are positioned in a proximal base 23 of the jaws in wrench head 19, and slots 46 are located in a distal region of jaw 16. Slots 42, 44 are oriented along a common arc of curvature centered at the center C of workpiece W (Fig. 3). (Center C is also the center of wrench head 19.) Slot 46 comprises a pair of lobes 48, 50. Inner lobe 48 is oriented along the same arc of curvature as slots 42, 44. Slots 42, 44 and inner lobe 48 of slot 46 each define an arc length of 10-12 degrees.
  • Outer lobe 50 of slot 46 is transverse to, and extends radially outwardly from, lobe 48. In particular, outer lobe 50 extends along an arc centered at a point 45 (Fig. 1) that corresponds to the center of pin 34 when the pin is positioned on the opposite side of slot 44 (shown as pin 34' in dashed lines in Fig. 1). As explained below, pin position 34' corresponds to the "unlocked" or ratcheting position of elongated plates 26, 28. Outer lobe 50 extends from a distal end at the distal end of inner lobe 48, to a proximal end that is radially spaced from that of inner lobe 48, along an arc length of 9-10 degrees. As a result, the overall configuration of slot 46 is V-shaped. Jaw 16 is enlarged with respect to jaw 17 in the manner discussed above to provide room for V-shaped slot 46 without unduly weakening jaw 16.
  • A leaf spring 50 (Fig. 2) is placed in base 23 of head 19 at the end of handle 18. One end 52 of leaf spring 50 is captured within an angled (with respect to the central longitudinal axis of handle 18) groove 54 in central plate 24. The opposite end 56 of leaf spring 50 engages the curved outer surface 27 of plate 26, thereby biasing plate 26 inwardly towards the center C of wrench head 19 and against workpiece W (Fig. 3).
  • When wrench 15 is in the position shown in Fig. 3, pin 36 engages the proximal ends of inner lobes 48 of slots 46, pin 34 engages the inner (with respect to opening 21) surfaces of slots 44 at the right-most ends (as seen in Fig. 3) of slot 44, and pin 32 is located at the distal ends of slots 42. Elongated plates 26, 28 thus are in a "locked" position and are immobile relative to each other when wrench 15 is turned in a driving direction D (e.g., clockwise, as shown in Fig. 3).
  • The operation of the wrench is described in more detail below with reference to the embodiment of Figs. 6-8. But briefly, after jaws 16, 17 are slid onto workpiece W from the side, wrench 15 is rotated in driving direction D to turn workpiece W. As handle 18 is turned in the driving direction, pressure develops between workpiece W and surfaces 30a of plates 26, 28. This pressure urges plates 26, 28 and pins 32, 36 outwardly and away from center C, and also urges the proximal ends of plates 26, 28 and pin 34 inwardly toward center C. These motions are prevented by the engagement of pins 32, 36 with the distal and proximal surfaces of slots 42, 46, and the engagement of pin against the inner and right-most end surfaces of slots 44. Accordingly, plates 26, 28 remain immobile with respect to each other in jaws 16, 17, grasp workpiece W between them at elongated surfaces 30a and rotate workpiece W in driving direction D.
  • When handle 18 is turned in the opposite (e.g., counterclockwise) direction from arrow D, ratcheting occurs. That is, plates 26, 28 slide over the surface of the workpiece, allowing the workpiece to remain stationary. This operation is explained in detail below with respect to Figs. 7 and 8. Briefly, however, when handle 18 is first rotated in the ratcheting direction, pins 32, 34 travel to an "unlocked" position at the opposite ends of respective slots 42, 44 along the common arc of curvature of the slots. That is, pins 32, 34 move to the proximal end of slot 42 and the left-most end of slot 44, respectively. Likewise, pin 36 moves within inner lobe 48 of slot 46 to the opposite (i.e., distal) end of lobe 48 (which also corresponds to one end of outer lobe 50, as discussed above). As a result, elongated plates 26, 28 rotate around center C with handle 18 until pins 32, 34, 36 reach the ends of slots 42, 44 and slot lobe 48, respectively. This operation requires approximately 10-12 degrees of handle rotation, which corresponds to the arc length of the slots.
  • With pins 32, 34, 36 positioned as just described, plates 26, 28 are "unlocked" and are ready for ratcheting. As handle 18 is rotated further counterclockwise (e.g. by 30 degrees for the 12-point configuration shown in Fig. 3), the engagement of plate 26 against workpiece W causes plate 26 to pivot outwardly from center C about centerpoint 45 (Fig. 1) of pin 34 as each corner of the workpiece slides across an elongated surface 30a or 30b of plate 26. Plate 28 remains stationary during the pivoting motion of plate 26. The pivoting motion of plate 26 is constrained by outer lobe 50 of slot 46. That is, pin 36 travels within outer lobe 50 as plate 26 pivots.
  • Leaf spring 50 biases plate inwardly toward center C. Thus, as the corners of the workpiece move toward notches 31, spring 50 urges plate 26 to pivot inwardly around centerpoint 45 of pin 34 in position 34', and back into full engagement with the workpiece surfaces. In the 12-point design shown in Fig. 3, approximately 30 degrees of handle rotation are needed to ratchet jaws 16, 17 around one corner of a hexagonal workpiece.
  • Because of the symmetrical construction of wrench 15, the driving and ratcheting direction can be reversed simply by turning wrench 15 over with respect to the workpiece (i.e., so that jaw 15 is on the right when viewed from above). In this orientation, the driving direction D is counterclockwise, and the ratcheting direction R is clockwise.
  • Other embodiments are within the scope of the following claims.
  • For example, the wrench may have elongated plates with more or fewer workpiece grasping surfaces.
  • Figs. 6-8 show a wrench 115 with so-called "6-point" design in which jaws 116, 117 respectively support elongated plates 126, 128 that each have two workpiece engaging surfaces 130. Surfaces 130 are each sufficiently long to engage a face of workpiece W along the entire length of the face. Surfaces 130 define an angle of 120° and a notch 131 therebetween. In other respects, wrench 115 is identical to wrench 15, and thus the other components of wrench 115 have been given the same reference numerals as the corresponding components of wrench 15.
  • In operation, after wrench 115 is inserted onto workpiece W from the side, handle 20 is turned in a driving direction (D, Fig. 6) (e.g., clockwise) to rotate workpiece W. As discussed above for wrench 15, plates 126, 128 are in the "locked" position because of the position of pins 32, 34, 36 in respective slots 42, 44, 46. Thus, as handle 20 is turned in direction D, pressure develops between workpiece W and surfaces 130 of plates 126, 128. This pressure urges plates 126, 128 and pins 32, 36 outwardly and away from center C, and the proximal ends of plates 126, 128 and pin 34 inwardly toward center C. This motion is prevented by the engagement of pins 32, 36 against the distal and proximal ends, respectively, of slots 42, 46, as well as by the engagement of pin 34 against the inner and right-hand end (as viewed in Fig. 6) of slot 34. Accordingly, plates 126, 128 remain immobile with respect to each other in jaws 116, 117, grasp workpiece W therebetween, and turn the workpiece in response to the handle rotation.
  • Referring to Fig. 7, the ratcheting operation is performed by turning handle 20 in the opposite direction R (counterclockwise, in this example). As handle 20 is first moved in direction R, pressure develops between workpiece W and surfaces 130 of plates 126, 128. This force causes pins 32, 34, 36 to slide to the opposite ends of slots 42, 44 and inner lobe 48 of slot 46, respectively, thereby causing plates 126, 128 to rotate within jaws 116, 117 along the common arc of curvature of these slots. When pins 32, 34, 36 reach the opposite ends of the respective slots (which occurs after approximately 10°-12° of handle rotation), elongated plates 126, 128 are in the "unlocked" position for ratcheting.
  • Referring to Fig. 8, further rotation of handle 20 in direction R around workpiece W causes additional pressure to be exerted against plates 126, 128 by workpiece W. This pressure causes plate 126 to pivot about pin 34 outwardly with respect to the workpiece and the remainder of jaw 116. This motion is constrained by pin 36, which travels in outer lobe 50 of slot 46. As a result, elongated surfaces 130 of plates 126, 128 slide around the corners of workpiece W, allowing the workpiece to remain stationary.
  • Once jaws 116, 118 have been rotated approximately 60° to a new ratcheting position (i.e., as a corner of the workpiece W slides into an adjacent notch 131), biasing spring 50 urges plate 126 to pivot inwardly about pin 34 so that pin 36 travels to its unlocked position at the distal end of lobes 48, 50. If further ratcheting is desired, the user continues to rotate handle 20 in direction R. Otherwise, the user resumes rotating handle 20 in driving direction D. For the initial few degrees of rotation in direction D, plates 126, 128 will not turn the workpiece but will instead rotate to their "locked" position as pins 32, 34, 36 move to the ends of the slots as shown in Fig. 6. Thereafter, further rotation of handle in the driving (e.g., clockwise) direction will cause plates 126, 128 to grasp and turn the workpiece.
  • Still other embodiments are within the scope of the claims.
  • For example, the positions of the distal pins and slots may be reversed. That is, referring to Fig. 3, pins 32, 36 may be formed in the face plates, and slots 42, 46 defined in the distal regions of plates 26, 28.
  • Figs. 9 and 10 show an open-end ratchet wrench 215 having such a reversed distal pin-slot construction. Wrench 215 is similar in construction to wrench 15, and includes a pair of arcuate jaws 216, 217 at the end of an elongated handle 218. Jaw 216 is somewhat larger than jaw 217 and protrudes more markedly from handle 218 than does jaw 217, for the reasons discussed above. Jaws 216, 217 and handle 218 are defined by a pair of face plates 220, 222, and a central plate 224 is sandwiched therebetween in handle 218 to provide space in jaws 216, 217 for a pair of elongated plates 226, 228. Elongated plates 226, 228 have the same curved shape as plates 26, 28 of wrench 15, and are movably mounted to face plates 220, 222 with the reversed distal pin-slot construction. That is, the distal slots are in elongated plates 226, 228 (rather than in the face plates that define jaws 216, 217), and the distal pins are secured to face plates 220, 222 (rather than to the elongated plates).
  • More specifically, elongated plate 228 includes a curved distal slot 242 that receives a pin 232 secured within round holes 231 in face plates 220, 222. A V-shaped distal slot 246 of elongated plate 226 includes a pair of lobes 248, 250 and receives a pin 236 which is secured within round holes 231 in face plates 220, 222. As will be appreciated by comparing Fig. 10 with Fig. 3, V-shaped slot 246 is arranged oppositely with respect to V-shaped slot 46 of wrench 15. That is, the base of the "V" of slot 246 is oriented toward the handle and the proximal end of elongated plate 226 (rather than away from the handle and toward the distal end of the plate, as is slot 46 in Fig. 3). A proximal pin 234 is secured within holes 233 in the proximal ends of plates 226, 228 (which, as discussed below, are aligned with each other) and is received by proximal slots 244 in face plates 220, 222 (only one of which is shown in Fig. 9).
  • Slots 242, 244 and lobe 248 of slot 246 are oriented along the same arc of curvature centered at workpiece center C and define an arc length of 10-12 degrees. Lobe 250 of slot 246 is transverse to and extends radially inwardly from lobe 248 along an arc centered at the center of hole 233 in plate 226 (see Fig. 11A) that corresponds to the center of pin 234. Lobe 250 curves radially inwardly toward the workpiece from a proximal end at the proximal end of lobe 248 to a distal end that is radially spaced from that of inner lobe 248, along an arc length of 9-10 degrees.
  • A leaf spring 250 (Fig. 10) is placed in base 223 of the wrench head at the end of handle 218. One end 252 of leaf spring 250 is captured within a groove 254 in central plate 224 (groove 254 is shown angled with respect to the central longitudinal axis of handle 218, but it may be straight instead). The opposite end 256 of leaf spring 250 engages the curved outer surface of elongated plate 226, thereby biasing plate 226 inwardly towards the center C of the wrench head and against workpiece W.
  • Elongated plates 226, 228 are shown apart from the remainder of wrench 215 in Figs. 11A and 11B (top views), Figs. 12A and 12B (side views), and Fig. 13 (a cross-sectional view). Except for their different distal slot configuration, plates 226, 228 are constructed identically to each other. As with the elongated plates of wrench 15, plates 226, 228 are kidney-shaped and provide a total of sixteen workpiece engaging surfaces 230a, 230b and eight cusps 230 arranged over an arc of 240 degrees. As a result, the arrangement of surfaces 230a, 230b on plates 226, 228 corresponds to a so-called "12-point" design. (That is, if the plates were to be extended to define a 360 degree figure, they would provide twelve cusps 230 or "points," and twenty four workpiece engaging surfaces 230a, 230b.) Surfaces 230a, 230b alternate with each other along plates 226, 228, as shown in Fig.s 11A and 11B.
  • The proximal end of each elongated plate 226, 228 is stepped-down in thickness at a shoulder 229 to define a shelf 229a at the base of the plate. Shelves 229a are approximately one-half of the nominal thickness T of each plate 226, 226. The regions of plates 226, 228 which include workpiece engaging surfaces 230a, 230b are thickened with integral flanges 237, 239, respectively, as best seen in Fig. 13 (the spacing between the elongated plates and face plates 220, 222 is shown exaggerated for ease of viewing). Flanges 237, 239 increase the contact area of surfaces 230a, 230b with the workpiece for increased strength.
  • Because of their identical shape, when plates 226, 228 are mounted within jaws 216, 217 with their elongated surfaces 230a, 230b facing each other, one plate (e.g., plate 226) will be face-up, and the other (plate 228) will be face-down. As a result, shelves 229a of the two plates will overlap with each other, with their holes 233 aligned in registry to receive pin 234.
  • The user operates wrench 215 in the same manner as described above for wrench 15. To briefly reiterate, after jaws 216, 217 are slid onto workpiece W from the side, wrench 215 is rotated in a driving direction (e.g., clockwise in Figs. 9 and 10) to turn workpiece W. Figs. 9 and 10 show wrench 215 in the "locked" position, in which pin 232 is located at the proximal end of slot 242, pin 234 is positioned at the right-most end of slot 244, and pin 236 is disposed at the distal end of slot lobe 248. As the user turns handle 218 in the driving direction, pressure develops between workpiece W and surfaces 230a of plates 226, 228. This pressure urges plates 226, 228 (and hence slot lobe 248 and slot 242, respectively) outwardly and away from center C, and also urges the proximal ends of plates 226, 228 and pin 234 inwardly toward center C. These motions are prevented by the engagement of the surfaces of slot 242 with pin 232, the engagement of the surfaces of slot lobe 248 against pin 236, and the engagement of pin 234 against the inner and right-most end surfaces of slots 244. Accordingly, plates 226, 228 remain immobile with respect to each other in jaws 216, 217, grasp workpiece W between them at elongated surfaces 230a, and rotate workpiece W in the driving direction.
  • When handle 218 is turned in the opposite (e.g., counterclockwise) direction, ratcheting occurs, in which plates 226, 228 slide over the surface of the workpiece, allowing the workpiece to remain stationary. Ratcheting is performed as follows. When handle 218 is first rotated in the ratcheting direction, pressure applied by the workpiece to engaging surfaces 230b causes plates 226, 228 to remain stationary while handle 218 rotates. As a result, slot 244 slides over pin 234 until pin 234 reaches position 234' at the left end of slot 244 (as shown in Fig. 9). At the same time, pins 232, 236 (which are held within jaw arms 216, 217) slide through slot 242 and slot lobe 248, respectively, along the common arc of curvature of the slots until pin 232 reaches the distal (i.e., upper) end of slot 242 and pin 236 reaches the proximal (i.e., lower) end of slot lobe 248. Movement of wrench 215 to this "unlocked" position (which can be thought of either as rotating plates 226, 228 clockwise relative to handle 218, or turning handle 218 counterclockwise relative to plates 226, 228) requires approximately 10-12 degrees of handle rotation, which corresponds to the arc length of the slots.
  • As handle 218 is rotated further counterclockwise (e.g. by 30 degrees for the 12-point configuration shown in Figs. 9 and 10), workpiece W exerts pressure against engagement surfaces 230b, which in turn applies an outwardly directed pressure against plate 226. This outward pressure causes plate 226 (and thus slot 246) to pivot outwardly from center C about centerpoint 245 (Fig. 9) of pin 234 in position 234' as each corner of the workpiece slides across an elongated surface 230a or 230b of plate 226. Plate 228 remains stationary during the pivoting motion of plate 226. The pivoting motion of plate 226 is constrained by lobe 250 of slot 246. That is, slot lobe 250 slides over pin 236 as plate 226 pivots.
  • Leaf spring 250 biases plate 226 inwardly toward center C. Thus, as the corners of the workpiece move toward notches 231, spring 250 urges plate 226 to pivot inwardly around centerpoint 245 of pin 234 in position 234', and back into full engagement with the workpiece surfaces. In the 12-point design shown in Fig. 9, approximately 30 degrees of handle rotation are needed to ratchet jaws 216, 217 around one corner of a hexagonal workpiece.
  • Because of the symmetrical construction of wrench 215, the driving and ratcheting direction can be reversed simply by turning wrench 215 over with respect to the workpiece (i.e., so that jaw 216 is on the right when viewed from above). In this orientation, the driving direction is counterclockwise, and the ratcheting direction is clockwise.
  • Among other advantages, placing distal slots 242, 246 in elongated plates 226, 228 allows V-shaped slot 246 (and hence pin 236) to be positioned radially further away from centerpoint C (i.e., toward the outer periphery of plate 226). In part, this is because lobe 250 of slot 248 curves inwardly toward the workpiece, rather than outwardly away from the workpiece (as with lobe 50 of wrench 15). As a result, less torque is applied to all of the pins 232-236 as they move peripherally, thereby reducing the risk of shearing the pins and adding to the overall strength of wrench 215.
  • It should also be noted that lobe 250 is smaller than lobe 50 of wrench 15 (Fig. 3), for the following reason. Although the curvature of each lobe 50, 250 is centered about the respective proximal pin, lobe 250 is located radially closer to proximal pin 234 than lobe 50 is to proximal pin 34. This allows lobe 250 to define a shorter length than lobe 50, even though the arc angles of two lobes are the same. Because of the relatively shorter length of lobe 250, it does not cut into lobe 248 as much as lobe 50 cuts into lobe 48. As a result, pin 236 is more fully seated within V-shaped slot 246, which reduces the chance of plate 226 being forced from lobe 248 to lobe 250 during driving. Moreover, because pins 232, 236 are secured at both ends to plates 220, 222, the pins are less likely to bend or diverge when wrench 215 applies large driving forces to the workpiece.
  • In addition to increasing the surface contact with the workpiece and increasing the strength of plates 226, 228, flanges 237, 239 reduce wear on both surfaces 230a, 230b and the workpiece surfaces. Moreover, as shown in Fig. 13, the workpiece is fully captured between plates 226, 228 to a completely seated position when wrench 215 is flush against a surface S that abuts workpiece W. This reduces the risk of wrench 215 slipping off of the workpiece.
  • Wrench 215 may have more or fewer workpiece engaging surfaces. For example, referring to Figs. 14A and 14B, elongated plates 226', 228' each have only two workpiece engaging surfaces 260. As discussed above, with this configuration, wrench 215 would have a so-called "6-point" design (as discussed above for Figs. 6-8). Each surface 260 includes driving portions 230a' and adjacent ratcheting portions 230b'. That is, during the driving operation, portions 230a' exert pressure against the workpiece to rotate the workpiece as handle 218 is turned. During ratcheting, the workpiece exerts pressure against portions 230b' to cause plate 226 to pivot.
  • Referring to Figs. 15A-15C and 16A-16B, the movable plates need not be identical or symmetrical with respect to the central longitudinal axis of the wrench. Wrench 315 has a pair of differently configured movable plates 326, 328 positioned in jaws 316, 317 at the distal end of handle 320. Plate 326 (shown apart from the wrench in Fig. 16A) is smaller than plate 328 (Fig. 16B). Either of the distal pin-slot arrangements discussed herein can be used in this embodiment. In the embodiment of wrench 315 shown in the figures, distal slots 342, 246 are in plates 326, 328, and distal pins 332, 336 are mounted in the face plates of the wrench.
  • Plates 326, 328 include proximal holes 333, which are aligned and receive proximal pin 334, which in turn passes through a proximal slot 344 in the face plates of the wrench. Wrench 315 operates in the same way as discussed above for wrench 314. Fig. 15A shows wrench 315 in the locked position, in which distal pin 336 is captured within lobe 348 of slot 346. Figs. 15B and 15C illustrate wrench 315 during ratcheting, in which distal pin 336 moves back and forth within lobe 350 of slot 346. (Figs. 15B and 15C are drawn as if the front face plate of the wrench has been removed, but the spring which engages plate 326, as in the other embodiments, is not shown.)
  • Among other advantages, proximal pin 334 is positioned relatively closely to slot lobe 350 compared with the other embodiments. This allows the length of lobe 350 to be reduced, and the angle between lobes 348, 350 to be increased. As a result, more material is present at the junction 360 (Fig. 16A) between the lobes, which provides greater holding power to maintain pin in lobe 348 (i.e., in the locked position) when the user applies large driving forces to the workpiece.
  • Referring to Figs. 17A-17E, the V-shaped distal slot of any of the embodiments of my wrench can be made smaller than has been illustrated in other figures. Consider, for example, plate 226 of wrench 215, which is shown in Fig. 17A. Fig. 17B shows how distal pin 236 moves in slot lobes 248, 250 when wrench 215 is moved between the "locked" and "unlocked" positions. It will be appreciated that pin 236 does not travel all the way to the base of the "V" shape. As illustrated in Fig. 17C, 246 could be reduced in size while still accommodating the motion of pin 236. The new configuration of slot 246', with lobes 248' and 250', is shown in Fig. 17D (and in plate 226 in Fig. 17E). Because of the small size of slot 246, during ratcheting plate 226 opens (i.e., pivots outwardly away from the workpiece) while the wrench is being rotated to the unlocked position, rather than remaining stationary until the plate is fully unlocked, as in the embodiments described above.
  • Among other advantages, reducing the size of the V-shaped slot minimizes the amount of material that is removed from the plate, which increases the strength of the wrench. In addition, the smaller slot more positively directs the distal pin around the junction 260' (Fig. 17E) between the lobes when the wrench is moved between the locked and unlocked positions. As a result, the pin is returned to the locked position even more positively than in the other embodiments.
  • Referring to Figs. 18A and 18B, the slot for the pivotable plate need not be dual lobed, as in previously described embodiments. Wrench 415 has a pair of differently configured elongated movable plates 426, 428 positioned in jaws 416, 417 at the distal end of handle 418. Plates 426, 428 include respective distal slots 446, 442, which receive distal pins 436, 432, respectively, mounted in the face plates 420, 422 of the wrench. Plates 426, 428 include proximal holes 433, which are aligned and receive proximal pin 434, which in turn passes through a proximal slot 444 in the face plates of the wrench. (Alternatively, as in previously-described embodiments, the positions of distal slots 442, 446 and pins 432, 436 can be reversed -- that is, distal slots 442, 446 can be formed in the wrench face plates, and pins 423, 436 can be affixed to plates 426, 428.)
  • Referring also to Fig. 19, the geometry of distal slots 442, 446 is shown in detail. Distal slot 442 of plate 428 includes a distal segment 442a that extends between points 470, 472, and a contiguous proximal segment 442b that extends between points 470, 474. Point 470 represents the position of the center of pin 432 at the junction between segments 442a, 442b, and points 472, 474 represent the positions of the center of pin 432 at opposite ends of segments 442a, 442b.
  • Distal segment 442a extends and is centered along an arc of curvature 476. Arc 476 is centered in the opening between the jaws at point C (the center of workpiece W), and measures 27 degrees between points 470, 472. Proximal segment 442b curves outwardly with respect to distal segment 442a and forms an approximately 3 degree extension of arc 476 proximally of point 470, so that the total arc length of slot 442 is 30 degrees. As a result of the outward curvature, point 474 is offset radially outwardly from the path defined by arc 476 (which is centered at the center of pin 434) by approximately 1-2 degrees (along an arc centered at the center of pin 434). Thus, when pin 432 moves between points 470, 474 in segment 442b, plate 428 simultaneously moves 3 degrees along arc 476 and 1-2 degrees inwardly toward the workpiece.
  • Distal slot 446 of plate 426 includes a proximal segment 446a that extends between points 480, 482, and a contiguous distal segment 446b that extends between points 482, 484. Point 482 represents the position of the center of pin 436 at the junction of segments 446a, 446b, and points 480, 484 represent the position of the center of pin 436 at the opposite ends of segments 446a, 446b. Slot 446 extends generally along an arc of curvature 486 that is concentric with arc 476 -- that is, arcs 476, 486 define different segments of a circle centered at point C. The arc length of slot 446 is also 30 degrees (27 degrees for segment 446a, 3 degrees for segment 446b). For purposes to be described, however, proximal segment 446a of slot 446 is transverse to arc 486 rather than being centered along arc 486. Specifically, proximal segment 446a spirals inwardly by approximately 7-8 degrees as segment 446a extends proximally from point 482 to point 480. As a result, point 480 is offset by an arc of approximately 7-8 degrees (centered at the center of pin 434) radially inwardly from the path defined by arc 486.
  • Distal segment 446b curves outwardly with respect to proximal segment 446a and forms an approximately 3 degree extension of arc 486 distally of point 470, so that the total arc length of slot 446 is 30 degrees. As a result of the outward curvature, point 484 is offset radially outwardly from the path defined by arc 486 by approximately 1-2 degrees (arc 486 is also centered at the center of pin 434). Accordingly, when pin 436 moves between points 482, 484 in segment 446b, plate 426 simultaneously moves 3 degrees along arc 486 and 1-2 degrees inwardly toward the workpiece.
  • Proximal slot 444 includes curved segments 444a, 444b (Fig. 18) centered along another segment of the same arc of curvature as arcs 476, 486. (That is, slot 444 and arcs 476, 486 are different segments of a circle centered at point C.) Unlike distal slots 442, 446, both segments of proximal slot 444 follow the same arc. Segment 444a defines an arc length of 27 degrees, and segment 444b forms a 3 degree extension of segment 444a for purposes to be described. Proximal slot 444 is positioned so that with elongated plates 426, 428 in their at-rest position (shown in Fig. 18A and discussed below), pin 434 is located at the junction of segments 444a, 444b.
  • Elongated plates 426, 428 are kidney-shaped, and each has distal and proximal workpiece engaging surfaces 430a, 430b that meet at a notch 431. As a result, the arrangement of surfaces 430a, 430b on plates 426, 428 corresponds to the "6-point" design discussed above. The overlapping, proximal ends of elongated plates 426, 428 are each stepped-down in thickness at a shoulder 429 to define a shelf 429a at the base of the plate. Shelves 429a are approximately one-half of the nominal thickness of each plate 426, 428. The proximal end 429a of plate 426 includes a hole 464 that receives one end of a coil spring 450. The opposite end of spring 450 is attached to a post 462 mounted in wrench handle 418 distal of center plate 424.
  • Referring to Figs. 20A-20C, spring 450 biases plates 426, 428 to their at-rest position, in which distal workpiece engaging surfaces 430a of plates 426, 428 are parallel to each other and are separated by a spacing S approximately equal to the width of the workpiece (Figs. 18, 20A). During use, the user engages wrench 415 with the workpiece (not shown) by sliding jaws 416, 417 onto the workpiece from the side. With plates 426, 428 in the positions shown (i.e., plate 426 on the left and plate 428 on the right), the user turns handle 418 in the clockwise direction (Fig. 20B) to drive or rotate the workpiece, and turns handle 418 in the counterclockwise direction (Fig. 20C) to perform the ratcheting operation.
  • Note that when plates 426, 428 are in their at-rest position, spring 450 positions pins 432, 434, 436 at the junctions between the pair of segments of respective slots 442, 444, 446 (the position of pin 444 is shown in Fig. 18A). In particular, pin 432 is located at point 470 (Fig. 19), and pin 436 is disposed at point 482.
  • As the user rotates the handle 3 degrees in the driving direction, the force applied against the workpiece compresses spring 450 and moves pins 432, 434, 436 to their fully seated positions at the opposite ends of slot segments 442b, 444b, 446b. Because segments 442b, 446b are positioned radially outwardly of respective arcs 476, 486, the movement of pins 432, 436 into segments 442b, 446b (to points 474, 484, respectively) causes elongated plates 426, 428 to pivot towards each other about pin 434 to grip the workpiece. In other words, the spacing S' between distal workpiece engaging surfaces 430a decreases from at-rest spacing S. Among other advantages, this gripping feature allows wrench 415 to firmly grasp and rotate a slightly undersized workpiece. In addition, the gripping action helps compensate for possible spreading apart by jaws 416, 417 as wrench 415 tightens the workpiece, which might otherwise allow plates 426, 428 to open slightly and slip over the workpiece.
  • The motion of plates 426, 428 during ratcheting is seen by comparing Figs. 20A and 20C. As the user rotates the handle counterclockwise from the at-rest position (Fig. 20A), the force applied against workpiece W causes pins 432, 434, 436 to travel in slots 442, 444, 446, against the biasing of spring 450, toward the opposite ends of slot segments 442a, 444a (Fig. 18), 446a. Because slot segment 442a is centered along arc 476 (Fig. 19), plate 428 moves in a circular path with respect to workpiece center C. In contrast, because slot segment 446a spirals inwardly with respect to arc 486 (Fig. 19), plate 426 pivots about pin 434 and spirals outwardly away from plate 428 and workpiece center C. In other words, plate 426 spreads apart from plate 428 by 7 degrees (the offset of point 480 from arc 486, Fig. 19), thereby allowing the workpiece engaging surfaces of plates 426, 428 to slide across the corners of the workpiece.
  • Fig. 20C shows plates 426, 428 in their fully open position during ratcheting. At this point, the user has rotated the wrench handle in the ratcheting direction by approximately 27 degrees (i.e., the arc length of slot segments 442a, 444a, 446a) away from the at-rest position (or 30 degrees from the gripping position shown in Fig. 20B). When the workpiece engaging surfaces have slid sufficiently around the corners of the workpiece, spring 450 returns plates 426, 428 to their at-rest position (Fig. 20A). The user may then either continue the ratcheting operation, or may instead drive the workpiece by rotating the handle clockwise.
  • One of the advantages of this embodiment of the wrench is additional manufacturing simplicity. Spiral slot 446 is easier to lay out and cut than, e.g., the V-shaped slots of the above-discussed embodiments, and may be more resistant to wear over the long term.
  • If the gripping feature is not desired, slot segments 442b, 444b, and 446b can be eliminated. (Or, alternatively, slot segments 442b and 446b can be positioned so that points 474, 484 lie on arcs 476, 486, respectively.
  • Features of wrench 415 may be applied to the other embodiments discussed herein. For example, extensions similar to slot segments 442b, 444b, 446b may be formed in the slots of the other embodiments of the wrench to provide the gripping feature.
  • Distal slot 446 may have other configurations in which point 480 is located radially inside of arc 486 (so that plate 426 pivots outwardly during ratcheting) and point 484 is positioned radially outside of arc 486 (to provide the gripping feature). For example, slot 446 can define a straight line between points 480 and 484.
  • Although only distal slot 446 has been described as being transverse to the arc of curvature 486 along which it generally extends, slot 442 may also (or instead) be oriented transversely to arc of curvature 476. For example, segment 442a may curve inwardly with respect to arc 476 so that point 472 (Fig. 19) is positioned radially inside of arc 476. Orienting both slots 442, 446 transversely to the arcs would allow both plates 426, 426 to pivot outwardly away from each other about pin 434 during ratcheting. As a result, the amount by which each plate pivots and the amount of handle rotation needed to move the plates to the fully open position during ratcheting can be reduced by half, thereby reducing the stresses applied to spring 450.
  • Fig. 21 shows a wrench 510 in which the distal slots 542, 546 of both plates 528, 526 are oriented transversely to the arcs of curvature 576, 586 along which the slots generally extend. Arcs 576, 587 are centered at the center C of the opening between jaws 516, 517. The proximal slot 544 (Fig. 23A) extends along the same arc of curvature as arcs 576, 586, and includes two concentric segments 544a, 544b.
  • The distal segment 542a of slot 542 is offset radially inwardly from arc 576 so that when pin 532 is positioned at the distal end of the slot (point 572), plate 528 is pivotable away from the workpiece about proximal pin 534. The proximal segment 542b of slot 542 is offset radially outside of arc 576 to provide the gripping feature discussed above when pin 532 is positioned at the proximal end of the slot (point 574). Pin 532 is shown located at the junction of segments 542a, 542b (point 570), which intersects arc 576.
  • Slot 546 is linear between its proximal and distal ends (defined by points 580, 584, respectively). The proximal segment 546a of slot 546 is positioned radially inwardly of arc 586 so that when pin 536 is positioned at the proximal end of the slot (point 580), plate 526 is pivotable away from the workpiece about proximal pin 534. The distal segment 546b of slot 546 is offset radially outside of arc 586 to provide the gripping feature discussed above when pin 536 is positioned at the distal end of the slot (point 584). Pin 536 is shown located at the junction of segments 546a, 546b (point 582), which intersects arc 586. The proximal end of plate 526 is connected to a spring similar to that shown in Fig. 18B.
  • The operation of wrench 510 is illustrated by Figs. 22A-22C and 23A-23C (which are identical except that the latter set of figures show the uppermost plate of wrench 510 and slot 544).
  • In the starting position (Figs. 22A, 23A), the spring (not shown) biases plates 526, 528 into their at rest position, with workpiece engaging surfaces 530a thereof oriented parallel to each other, and pins 532, 534, 536 are located at the junctions of the two segments of respective slots 542, 544, 546. As shown in Figs. 22B, 23B, when the user rotates the wrench handle in the clockwise direction (e.g., by 3 degrees as discussed above for wrench 415), pins 542, 544, 546 are moved into slot segments 542b, 544b, 546b, thereby providing the gripping action against the workpiece (not shown) discussed above.
  • When the user rotates the handle in the opposite direction, as shown in Figs. 22C, 23C, the forces applied against the workpiece engaging surfaces by the workpiece cause pins 532, 534, 536 to travel to the opposite ends of respective slots 542, 544, 546. In particular, pins 532, 536 are moved to the distal and proximal ends, respectively, of slot segments 542a, 546a. Because the distal end of slot segment 542a and the proximal end of slot segment 546a are positioned radially inwardly of arcs 576, 586, the movement of pins 532, 536 therein causes each plate 526, 528 to pivot outwardly away from center C. After the wrench handle has been rotated sufficiently (e.g., by 45 degrees) to slide the workpiece engaging surfaces sufficiently around the corners of the workpiece, the spring returns plates 526, 528 to their at-rest position (Figs. 22A, 23A).
  • In other embodiments, the elongated surfaces of the movable plates may be curved (e.g., convex with respect to opening 21) rather than flat. Other numbers and angular arrangements of elongates surfaces may be used.
  • The wrench handle need not be in-line with, or in the same plane as, the jaws, as is shown in the figures. Instead, as is typical with open-end wrenches, the handle may be offset at an acute angle to the jaws, either in the plane of the jaws, or out of the plane of the jaws, or both. The groove for the biasing spring may be parallel to the handle axis; indeed, the spring may be fixed to the handle in other ways.

Claims (68)

  1. A wrench comprising
    a pair of jaws disposed on a handle, the jaws being spaced to define an opening for a workpiece, and
    a pair of plates each of which includes a workpiece engaging surface adjacent the opening, the plates being mounted on the jaws for selective movement between:
    a) a first position in which the plates are substantially immobile with respect to each other so that rotation of the handle in a first direction causes the plates to grasp the workpiece between the engaging surfaces and turn the workpiece in the first direction, and
    b) and a second position in which a first one of the plates is pivotable with respect to a second one of the plates so that rotation of the handle in a second, opposite direction causes pivoting of the first plate and allows the engaging surfaces to slide over the workpiece, thereby allowing the workpiece to remain stationary.
  2. The wrench of claim 1 wherein the plates are mounted for the selective movement in response to rotation of the handle.
  3. The wrench of claim 1 in which the first plate has a proximal end and a distal end, the first plate being mounted to a first one of the jaws so that the distal end is substantially immobile in the first position, and is pivotable with respect to the second plate in the second position.
  4. The wrench of claim 3 further comprising
    a distal pin on one of the distal end of the first plate or a distal region of the first jaw, and
    a distal slot disposed in the other one of the distal end of the first plate or the distal region of the first jaw,
    the distal pin being disposed in a first portion of the distal slot when the plate is in the first position, and being disposed in a second portion of the distal slot when the plate is in the second position.
  5. The wrench of claim 4 wherein the first portion of the distal slot is oriented so that the engagement of the distal pin therein holds the distal end of the first plate substantially immobile with respect to the second plate when the wrench is rotated in the first direction, and the second portion of the distal slot is oriented to allow the distal end of the first plate to pivot with respect to the second plate when the wrench is rotated in the second direction.
  6. The wrench of claim 5 further comprising a proximal pin on the proximal end of the first plate received by a proximal slot disposed in a proximal region of the first jaw, the proximal slot and the first portion of the distal slot being oriented to allow the selective movement of the first plate between the first position and the second position.
  7. The wrench of claim 6 wherein the proximal slot and the first portion of the distal slot are oriented along a common arc of curvature having a center disposed in the opening, and the second portion of the distal slot is arranged transversely to the arc of curvature.
  8. The wrench of claim 4 or 6 wherein the distal pin is on the distal end of the first plate and the distal slot is disposed in the distal region of the first jaw.
  9. The wrench of claim 4 or 6 wherein the distal pin is on the distal region of the first jaw and the distal slot is disposed in the distal end of the first plate.
  10. The wrench of claim 6 further comprising a distal pin at a distal end of the second plate received by a distal slot disposed in a distal region of the second jaw, and a proximal pin on a proximal end of the second plate received by the proximal slot, the proximal slot and the distal slot being oriented to allow the selective movement of the second plate between the first position and the second position.
  11. The wrench of claim 4 wherein said distal slot is arranged so that the first and second portions thereof generally define a "V" shape.
  12. The wrench of claim 11 wherein said distal slot is arranged so that a base of the "V" shape is oriented toward the handle.
  13. The wrench of claim 11 wherein said distal slot is arranged so that a base of the "V" shape is oriented away from the handle.
  14. The wrench of claim 1 further comprising a spring positioned to bias the first plate toward the opening.
  15. The wrench of claim 14 wherein the plates and the spring are arranged so that turning the wrench over with respect to the workpiece reverses operation of the wrench in the first and second directions.
  16. The wrench of claim 1 wherein the plates are identically configured.
  17. The wrench of claim 1 wherein the plates are differently configured.
  18. The wrench of claim 1 wherein each of the plates has a plurality of the engaging surfaces.
  19. The wrench of claim 18 wherein each of the engaging surfaces is elongated so as to engage a face of the workpiece over a major portion of a length of the face.
  20. The wrench of claim 18 wherein said engaging surfaces are flat.
  21. The wrench of claim 18 wherein the engaging surfaces are arranged to define an angle therebetween equal to an angle between adjacent faces of the workpiece.
  22. The wrench of claim 1 wherein a portion of each plate that includes the engaging surface has an enlarged thickness relative to another portion of the plate.
  23. The wrench of claim 1 wherein the plates are mounted on the jaws so that when in the first position the plates are substantially immobile with respect to each other in that the plates cannot spread apart from each other.
  24. The wrench of claim 23 in which one of the plates is mounted so that when in the first position a distal end thereof is movable toward the other one of the plates.
  25. The wrench of claim 23 in which the plates are mounted so that when in the first position distal ends thereof are movable toward each other.
  26. The wrench of claim 1 further comprising
    a distal pin on one of a distal end of the first plate or a distal region of the first jaw, and a distal slot disposed in the other one of the distal end of the first plate or the distal region of the first jaw,
    the distal slot being oriented transversely to an arc of curvature centered in the opening, with a first portion of the distal slot intersecting the arc and a second portion of the distal slot being positioned radially inside of the arc,
    the distal pin being disposed in the first portion of the distal slot in the first position, and being movable into the second portion of the distal slot in the second position to cause the first plate to pivot with respect to the second plate.
  27. The wrench of claim 26 wherein the first portion of the distal slot is at a distal end thereof, and the second portion of the first distal slot is at a proximal end thereof.
  28. The wrench of claim 26 wherein the first portion of the distal slot is at a proximal end thereof, and the second portion of the distal slot is at a distal end thereof.
  29. The wrench of claim 26 wherein the first and second portions of the distal slot are curved.
  30. The wrench of claim 26 wherein the first and second portions of the distal slot are straight.
  31. The wrench of claim 26 wherein the distal slot further comprises a region oriented to receive the distal pin and cause the first plate to move toward the second plate and further grip the workpiece when the handle is rotated in the first direction.
  32. The wrench of claim 31 wherein said region of the distal slot is positioned radially outside of the arc.
  33. The wrench of claim 32 wherein the first portion and said region are at a distal end of the distal slot, and the second portion is at a proximal end of the distal slot.
  34. The wrench of claim 32 wherein the first portion and said region are at a proximal end of the distal slot, and the second portion is at a distal end of the distal slot.
  35. The wrench of claim 26 further comprising a proximal pin on proximal end of the first plate received by a proximal slot disposed in a proximal region of the first jaw, the proximal pin being disposed in a first portion of the proximal slot in the first position, and being movable into a second portion of the proximal slot in the second position, the first plate pivoting about the proximal pin away from the second plate in the second position.
  36. The wrench of claim 35 wherein the first and second portions of the proximal slot are oriented along the arc.
  37. The wrench of claim 26 further comprising
    a second distal pin on one of a distal end of the second plate or a distal region of the second jaw, and a second distal slot disposed in the other one of the distal end of the second plate or the distal region of the second jaw,
    the second distal pin being disposed in a first portion of the second distal slot in the first position, and being movable into a second portion of the second distal slot in the second position.
  38. The wrench of claim 37 wherein the first portion of the second distal slot is at a proximal end thereof, and the second portion of the second slot is at a distal end thereof.
  39. The wrench of claim 37 wherein the first portion of the second slot is at a distal end thereof, and the second portion of the second distal slot is at a proximal end thereof.
  40. The wrench of claim 37 wherein the second distal slot is oriented along the arc so that the second plate does not pivot with respect to the first plate as the second distal pin moves from the first portion to the second portion of the second distal slot.
  41. The wrench of claim 37 wherein the second distal slot is oriented transversely to the arc, with the first portion thereof intersecting the arc and the second portion thereof being positioned radially inside of the arc, so that the second plate pivots with respect to the first plate as the second distal pin moves from the first portion to the second portion of the second distal slot.
  42. The wrench of claim 41 wherein the first and second portions of the second distal slot are curved.
  43. The wrench of claim 41 wherein the first and second portions of the second distal slot are straight.
  44. The wrench of claim 41 wherein the second portion of the first mentioned distal slot and the second portion of the second distal slot are located at opposite ends of the respective distal slots.
  45. The wrench of claim 41 wherein each of the distal slots further comprises a region oriented to receive the respective distal pin and cause the first and second plates to move toward each other and further grip the workpiece when the handle is rotated in the first direction.
  46. The wrench of claim 45 wherein said regions are positioned radially outside of the arc and are located at opposite ends of the respective distal slots.
  47. The wrench of claim 41 further comprising a proximal pin on proximal end of the first and second plates received by a proximal slot disposed in a proximal base of the jaws, the proximal pin being disposed in a first portion of the proximal slot in the first position, and being movable into a second portion of the proximal slot in the second position, the first and second plates pivoting about the proximal pin away from each other in the second position.
  48. The wrench of claim 47 wherein the first and second portions of the proximal slot are oriented along the arc.
  49. The wrench of claim 26 further comprising a spring positioned to bias the first plate to return from the second position toward the first position.
  50. A wrench comprising
    first and second jaws disposed on a handle, the jaws being spaced to define an opening for a workpiece,
    first and second plates respectively associated with said first and second jaws, each of said plates including a workpiece engaging surface adjacent the opening,
    a pair of distal pins each of which is associated with one of said jaws, each one of said pins being fixedly mounted to one of the respective jaw or plate and being received in a corresponding slot disposed in the other one of said respective jaw or plate, and
    a proximal pin mounted to the first and second plates and received in a proximal slot disposed in a proximal region of the jaws,
    the pins and slots being arranged to allow selective movement of the plates between:
    a) a first position in which the pins are positioned in the slots to hold the plates substantially immobile with respect to each other so that rotation of the handle in a first direction causes the plates to grasp the workpiece between the engaging surfaces and turn the workpiece in the first direction, and
    b) and a second position in which the pins are positioned in the slots so that the first plate is pivotable with respect to the second plate so that rotation of the handle in a second, opposite direction
    causes pivoting of the first plate and allows the engaging surfaces to slide over the workpiece, thereby allowing the workpiece to remain stationary; and
    a spring positioned to bias the first plate toward the opening.
  51. The wrench of claim 50 wherein the distal slot associated with the first jaw has a first portion and a second portion, the first portion being oriented so that the engagement of the corresponding pin therein holds the distal end of the first plate substantially immobile with respect to the second plate when the wrench is rotated in the first direction, and the second portion being oriented to allow the distal end of the first plate to pivot with respect to the second plate when the wrench is rotated in the second direction.
  52. The wrench of claim 51 wherein the proximal slot, the first region of the distal slot associated with the first jaw, and the distal slot associated with the second jaw are oriented along a common arc of curvature having a center disposed in the opening, and the second portion of the distal slot associated with the first jaw is arranged transversely to the arc of curvature.
  53. The wrench of claim 52 wherein the distal pins are fixedly mounted on the plates and the distal slots are disposed in the jaws.
  54. The wrench of claim 52 wherein the distal pins are fixedly mounted on the jaws and the distal slots are disposed in the plates.
  55. The wrench of claim 51 wherein said distal slot associated with the first jaw is arranged so that the first and second portions thereof generally define a "V" shape.
  56. The wrench of claim 55 wherein said distal slot is arranged so that a base of the "V" shape is oriented toward the handle.
  57. The wrench of claim 55 wherein said distal slot is arranged so that a base of the "V" shape is oriented away from the handle.
  58. The wrench of claim 50 wherein the plates and the spring are arranged so that turning the wrench over with respect to the workpiece reverses operation of the wrench in the first and second directions.
  59. The wrench of claim 50 wherein the plates are identically configured.
  60. The wrench of claim 50 wherein the plates are differently configured.
  61. The wrench of claim 50 wherein a portion of each plate that includes the engaging surface has an enlarged thickness relative to another portion of the plate.
  62. A wrench comprising
    first and second jaws disposed on a handle, the jaws being spaced to define an opening for a workpiece,
    first and second plates respectively associated with said first and second jaws, each of said plates including a workpiece engaging surface adjacent the opening,
    a first distal pin on one of the distal end of the first plate or a distal region of the first jaw, disposed in a first distal slot in the other one of the distal end of the first plate or the distal region of the first jaw,
    a second distal pin on one of the distal end of the second plate or a distal region of the second jaw, disposed in a second distal slot in the other one of the distal end of the second plate or the distal region of the second jaw, a portion of the second slot being oriented along an arc of curvature having a center disposed in the opening,
    the first distal slot being oriented so that a distal portion thereof is positioned on the arc and a proximal portion thereof is positioned radially inside of the arc,
    a proximal pin mounted to the first and second plates and received in a proximal slot disposed in a proximal region of the jaws and oriented along the arc,
    the pins being movable within the respective slots to allow selective movement of the plates between:
    a) a first position in which the pins are positioned in the slots to hold the plates substantially immobile with respect to each other so that rotation of the handle in a first direction causes the plates to grasp the workpiece between the engaging surfaces and turn the workpiece in the first direction, and
    b) and a second position in which the pins are positioned in the slots so that the first plate is pivotable with respect to the second plate so that rotation of the handle in a second, opposite direction causes pivoting of the first plate and allows the engaging surfaces to slide over the workpiece, thereby allowing the workpiece to remain stationary.
  63. The wrench of claim 62 wherein the first distal pin is disposed at the distal portion of the first distal slot when the first plate is in the first position, and is disposed at the proximal portion of the first distal slot when the first plate is in the second position.
  64. The wrench of claim 62 in which the first and second distal slots and the proximal slot have regions oriented to receive the respective pins and cause the first and second plates to move toward each other and further grip the workpiece when the handle is rotated in the first direction with the plates in the first position.
  65. The wrench of claim 64 wherein said regions are disposed at opposite ends of the respective the distal slots and are positioned radially outside of the arc.
  66. The wrench of claim 64 wherein said region of the proximal slot is positioned along the arc.
  67. The wrench of claim 62 wherein the second distal slot includes a second portion that is positioned radially inside of the arc, so that the second plate pivots with respect to the first plate as the second distal pin moves from the first mentioned portion to the second portion of the second distal slot.
  68. The wrench of claim 62 further comprising a spring positioned to bias the first plate to return from the second position toward the first position.
EP19990301595 1998-03-06 1999-03-03 Open end ratchet wrench Withdrawn EP0940225A2 (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
US36349 1998-03-06
US09/036,349 US6223630B1 (en) 1998-03-06 1998-03-06 Open end ratchet wrench
US11462898A true 1998-07-13 1998-07-13
US25105099A true 1999-02-18 1999-02-18
US114628 1999-02-18

Publications (1)

Publication Number Publication Date
EP0940225A2 true EP0940225A2 (en) 1999-09-08

Family

ID=27365018

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19990301595 Withdrawn EP0940225A2 (en) 1998-03-06 1999-03-03 Open end ratchet wrench

Country Status (2)

Country Link
EP (1) EP0940225A2 (en)
TW (1) TW386050B (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI379739B (en) 2010-12-06 2012-12-21 Jyun Wun Liao Sleeve structure for a spanner
TWI415717B (en) * 2010-12-15 2013-11-21 Dess Ind Co Ltd Open-ended ratchet wrenth
TWI398324B (en) * 2011-08-12 2013-06-11 Proxene Tools Co Ltd Ratchet-action open-end wrench
CN102950555B (en) * 2011-08-18 2015-04-01 伯鑫工具股份有限公司 Open-end wrench capable of ratcheting reciprocatingly
TWI464036B (en) * 2012-09-25 2014-12-11 Kabo Tool Co A multipurpose reciprocating wrench

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TW386050B (en) 2000-04-01

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