MXPA00005517A - Sealed reversible ratchet wrench - Google Patents

Abstract

A reversible ratchet wrench (10) including a ratchet body (11) having a round head portion (12) with a cylindrical, internally toothed opening (13). A ratchet mechanism, including a drive body (20) is disposed in the opening. A reversing member (43) is secured to the body to confine a pawl assembly (30). An annular shoulder surface on the ratchet body faces a corresponding annular shoulder surface on the reversing member. A second annular shoulder surface on the ratchet body faces a corresponding annular shoulder surface on the drive body. Annular seal members (80, 80A), each having a pair of radially inwardly extending and axially diverging flexible and resilient lips, are located between the corresponding sets of annular shoulder surfaces.

Description

SEALED REVERSIBLE WRENCH WRENCH BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to ratchet mechanisms and in particular ratchet wrenches of the reversible type, having a manually operated reversing member. The invention relates in particular to seals for the ratchet mechanism. Description of the Prior Art The present invention is an improvement of the reversible ratchet wrench described in US Pat. No. 5,495,783, the description of which is incorporated herein by reference. Accordingly, both the construction of the ratchet wrench will be described in detail herein, as necessary to understand the present invention. In the key of the U.S. patent No. 5,495,783, a handle with a circular ratchet head has a cylindrical set of internal ratchet teeth defining a cavity, which receives a pulse body coaxially rotating. A detent is transported by the impulse body for movement between advancing and reversing conditions of engagement with the ratchet teeth, retained in each of these positions by a spring on the center, which engages with a pin in an inversion lever . The reversing lever is placed coaxially with the thrust body and retained there by a bushing and a screw for rotation with respect to the thrust body and the ratchet head to move the detent between its advance and reverse conditions. Annular recesses are formed at each end of the head coaxial with the cavity and respectively face corresponding annular recesses in the drive body and reversing lever, to cooperate with it, in order to define annular spaces where annular seal members respectively are received. to retain lubricant in the cavity and prevent the entry of dust and dirt there. The seals are radial seals, with each seal disposed between and resiliently engaging opposite cylindrical surfaces of the corresponding recesses. It has been found that the radial compression force on the radial seals, necessary to maintain an effective seal creates a significant frictional drag on the rotating parts, requiring a significant torque to perform both the locking operation and the manual operation of the member. investment. SUMMARY OF THE INVENTION A general objective of the present invention is to provide an improved sealed ratchet structure, which avoids the disadvantages of prior ratchet structures while providing additional structural and operational advantages. An important feature of the invention is to provide a sealed ratchet structure, which provides an effective seal while at the same time minimizing frictional drag on the rotating parts. In connection with the above feature, a further feature of the invention is to provide a ratchet structure of the established type, which is of a relatively simple and inexpensive construction. Certain of these and other features of the invention can be achieved by providing a sealed ratchet structure, comprising: a ratchet body with a cylindrical through opening having an axis and defining a cavity, a first annular shoulder surface formed in the body ratchet at one end of the coaxial cavity and extending parallel to a plane disposed substantially perpendicular to the axis, a ratchet mechanism mounted in the cavity and including an impeller member mounted for rotation relative to the ratchet body relative to the axis and having a second annular shoulder surface which directs the first annular shoulder surface substantially parallel thereto, coaxial and cooperating to define an annular space therebetween, a seal member disposed in the annular space and having two lips that extend radially and spaced axially flexible and resilient, respectively coupled with the shoulder surfaces to cooperate in order to seal the end of the cavity. Other features of the invention can be achieved with a sealed reversible ratchet structure comprising: a ratchet body with a cylindrical through opening having an axis and defining a cavity, first and second annular shoulder surfaces formed in the ratchet body respectively in first and second ends of the coaxial cavity and extending parallel to a plane disposed substantially perpendicular to the axis, the ratchet mechanism is mounted in the cavity, the ratchet mechanism includes a pulse member mounted for rotation relative to the ratchet body with relation to the axis, and having a third annular shoulder surface, facing the first substantially parallel and coaxial annular shoulder surface to cooperate in order to define a first annular space therebetween, the ratchet mechanism includes an inverting member mounted for rotation relative to the ratchet body with respect to the y axis that has a fourth annular shoulder surface facing the second annular shoulder surface substantially parallel and coaxial for cooperation in order to define a second annular space therebetween, a first seal member disposed in the first annular space and having two lips extending radially and axially flexible and resilient spacing, respectively coupling the first and third shoulder surfaces for cooperation in order to seal the first end of the cavity, and a second seal member disposed in the second annular space and having two flexible lips and resilient radially extending and axially spaced, respectively coupling the second and fourth shoulder surfaces for cooperation in order to seal the second end of the cavity. The invention consists of certain novel features and a combination of parts which will now be fully described, illustrated in the accompanying drawings and particularly pointed out in the appended claims, it being understood that various changes in details may be made without departing from the spirit or sacrificing any of the advantages of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS In order to facilitate an understanding of the invention, a preferred embodiment thereof is illustrated in the accompanying drawings, from an inspection of which when considered in connection with the following description, the invention, its construction and operation and many of its advantages should be understood and appreciated easily. Figure 1 is a top plan view of a ratchet wrench constructed in accordance with and embodying the features of the present invention; Figure 2 is an enlarged view in vertical section, taken on line 2-2 of Figure 1; Figure 3 is a further enlarged fragmentary sectional view of the portion designated 3 in Figure 2; and Figure 4 is a further enlarged fragmentary sectional view of the portion designated 4 in Figure 2. DESCRIPTION OF THE PREFERRED MODALITY Referring to FIGS. 1 and 2, a reversible ratchet wrench, generally designated by the numeral 10, is constructed in accordance with and embodying the features of the present invention. The ratchet wrench 10 has an elongated handle 11 having unitarily formed at one end a circular ratchet head 12, having an enlarged circular opening or bore 13 formed axially through and defining a cavity. A cylindrical set of equiangularly spaced ratchet teeth (not shown) is formed on the inner surface of the perforation 13. The perforation 13 extends between opposite lateral surfaces of the head 12. Also with reference to Figures 3 and 4, the opposite lateral surfaces of the head 12, respectively, have recessed recesses or recessed holes 14 and 17 formed, the recess 14 has a planar substantially planar annular end surface 15 and cylindrical lateral surface 16, both substantially coaxial with the perforation 13. Similarly, the recess 17 has a planar annular end surface 18 and a cylindrical lateral surface 19 both of which are substantially coaxial with each other. the bore 13. Arranged coaxially in the bore 13 for rotation about its axis relative to the head 12, there is an impeller body 20 having a square impulse lug 21 unitary at one end and projecting axially therefrom for coupling with an associated driven member such as a cavity, all in a known manner. The pulse lug 21 can be provided with a detent detent ball (not shown), also in known manner. Also with reference to Figure 3, the thrust body 20 is provided with a radially outwardly extending annular flange 22 dimensioned to be received in the annular recess 14 of the ratchet head 12. The flange 22 in turn has a annular recess 23 formed, which includes a substantially planar annular end surface 24 and a cylindrical side surface 25, both arranged to be substantially coaxial with the bore 13 in the assembled condition of the pieces. The pulse body 20 has an end surface 26 formed at the other axial end opposite the pulse lug 21, the pulse body 20 is dimensioned such that the end surface 26 is positioned axially inward of the annular recess 17 when the annular flange 22 sits in the annular recess 14 as illustrated in Figure 2. The end surface 26 has a deep detent recess 27 therein formed on one side. At the end surface 26, a shallow pin recess 28 is formed on its opposite side. Also at the end surface 26, the recess 27 and the pin recess 28 substantially axial to the pulse body 20 are formed intermediate, a substantially rectangular recess 29. Centrally formed in the rectangular recess 27 and coaxially with the drive body 20 is the internally threaded cylindrical bore 29a. Seated in the detent recess 27 is a retainer 30. Shaped on the outer side of the retainer 30 is an arcuate set of teeth (not shown) facing and dimensioned for meshing engagement with the ratchet teeth of the head 12. Formed in the opposite side of the retainer 30 is a flat rear surface 32 dimensioned for sliding engagement with the axial wall of the recess of the retainer 27. The set of detent teeth and the rear surface 32 thereof extend between flat and parallel top and bottom surfaces. 33 and 34 of the retainer 30. Also with reference to Figure 4, the ratchet wrench 10 is likewise provided with an immersion lever 40, generally in the form of a circular disk having an axial bore 41 formed through and encircled in its upper end with an annular recess 42. Formed on the outer surface of the reversing lever 40 are three ribs equiangularly spaced and extending from each other. nden radially 43. Depending on the inner surface of the reversing lever 40 and spaced a predetermined distance radially outwardly of the bore 41 is a cylindrical pin 45, which is preferably unitary with the lever 40. Formed on the outer surface of the dip lever 40, radially just outside the recess 42 and at angularly spaced locations, there are on and off signals (ON and OFF) 44 and 46. The reversing lever 40 is dimensioned to seat in the recess 17 of the head 12, the reversing lever 40 has an annular recess 47 on the inner surface at its outer edge, defining a planar annular end surface 48 and a cylindrical lateral surface 49, both substantially coxial with the bore 41. The reversing lever 40 is placed on the head 12, such that the pin 45 is received in the recess of the pin 28, the bore 41 is coaxial with the pulse body 20. The ratchet wrench 10 also includes a cylindrical bushing 50 sized to be received through the bore 41 of the reversing lever 40 and in a rectangular recess 29 of the thrust body 20. In this case For example, the bushing 50 has flat portions (not shown) formed on diametrically opposed sides adjacent to its distal end. In this way, it will be appreciated that the distal end of the bushing 50 is keyed or received non-rotatably in the rectangular recess 29. The bushing 50 is provided adjacent its outer end with a radially outwardly extending annular flange 53, which is supported in the recess 42 of the reversing lever 40 when the distal end of the bushing 50 is keyed in the rectangular recess 29. The flange 53 has an indicator 54 formed on its outer surface (FIG. 1). A screw 55 is received through the bushing 50 for threaded engagement in the threaded bore 29a, the screw 55 has an enlarged head 56 which abuts against the annular flange 53. In this way, it will be appreciated that the screw 55 cooperates with the bushing 50 to hold the ratchet wrench parts 10 in an assembled condition, retaining the thrust body 20 in the annular recess 14 and retaining the reversing lever 40 in the annular recess 17 of the ratchet head 12. The ratchet wrench 10 also includes a bypass spring 60 in the form of an elongated wire spring member, having a generally heart-shaped configuration, which includes a pair of opposing lobes 62 (one shown) and a cusp 65, all placed in a plane substantially perpendicular to the axis of the pulse body 20 between the reversing lever 40 and the impulse body 20. Units with the lobes 62 at their opposite ends at the apex 65 are ex- anchor treads 66 (one shown in Figure 2) extending to a bore (not shown) of the retainer 30. The arrangement and operation of the ratchet wrench parts 10 described above is shown more fully in the patent of the USA No. 5,495,783 previously mentioned. With particular reference to Figures 3 and 4 of the drawings, a significant aspect of the invention is that when the parts are assembled, the annular recesses 14 and 17 in the ratchet head 12 respectively cooperate with the annular recess 23 of the impulse body. 20 and the annular recess 47 of the reversing lever 40, to define annular spaces 70 and 75, respectively accommodating annular seals 80 and 80A which are substantially identical in construction, with which only one will be described in detail. Each of the seals 80, 80A is formed of a suitable resilient flexible material and has a body 81 that is generally rectangular in cross section, with a generally cylindrical outer end wall 82 and annular top and bottom walls 83 and 84. Units with the body 81 and extending radially inward are two axially diverging lips 85 and 86 respectively extending above and below the top and bottom walls 83 and 84. In use, the seal 80 is placed in the annular space 70, with the lips 85 and 86 respectively engaging the annular end surface 15 of a ratchet head 12 and the annular end surface 24 in the pulse body 20. Similarly, the seal 80A is placed in the annular space 75, with the lips 85 and 86 respectively engaging the annular end surface 48 of the reversing lever 40 and the annular end surface 18 of the ratchet head 12. In this way When the parts are clamped together with the screw 55, the lips 85 and 86 of the seals 80 and 80A are compressed slightly in an axial direction. Accordingly, the seals 80 and 80A are axial seals, exerting seal forces in axial directions to seal the lubricant in the cavity formed by the bore 13 and to prevent ingress of dust or dirt into the interior. It has been found that this axial seal structure exerts substantially less rotational drag on the assembled parts than the radial seals of the prior art. This is considered to result at least in part from the fact that the double lip seal arrangement minimizes the surface contact between the seals 80 and 80A on the other hand, and the associated annular surfaces defining an annular space 70 and 75, on the other hand part. It will be appreciated that, because of this axial compressive force, the seals 80 and 80A serve as bypass members cooperating to resiliently center the ratchet head 12 relative to the thrust body 20 and the reversing lever 40, to avoid dragging or wear. Excessive on either side of the ratchet head 12. In a preferred embodiment of the invention, the seals 80 and 80A, are formed of a material that is easily molded and retains its yield over a wide range of temperatures, even when in contact with petroleum base lubricants. This material may be a nitrile polymer, although it will be appreciated that other suitable materials may be used. From the foregoing, it can be seen that an improved reversible ratchet wrench and its seals have been provided, which provides an effective seal while minimizing frictional snatching and at the same time operating as compression springs to axially center the parts. While particular embodiments of the present invention have been illustrated and described, it will be apparent to those skilled in the art that changes and modifications can be made without departing from the invention in its broader aspects. Therefore, the aim in the appended claims is to cover all these changes and modifications that fall within the spirit and actual scope of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only and not as a limitation. The current scope of the invention is intended to be defined in the following claims when viewed in its proper perspective based on the prior art.

Claims (17)

1. - A sealed ratchet structure, characterized in that it comprises: a ratchet body with a cylindrical through opening having an axis and defining a cavity, a first annular shoulder surface formed in the ratchet body at one end of the coaxial cavity and extends parallel to a plane disposed substantially perpendicular to the shaft, ratchet mechanism mounted in the cavity and including a driver member mounted for rotation relative to the ratchet body with respect to the shaft and having a second annular shoulder surface facing the first surface of substantially parallel and coaxial annular shoulder and cooperates to define an annular space therebetween and a seal member disposed in the annular space and having two resilient and flexible lips radially extended and axially spaced that engage with the shoulder surfaces to cooperate in sealing the end of the cavity.

2. The structure according to claim 1, characterized in that the seal member includes an annular seal body from which the lips extend.

3. The structure according to claim 2, characterized in that the lips diverge from the seal body.

4. - The structure according to claim 2, characterized in that the lips extend radially inwardly from the seal body.

5. - The structure according to claim 4, characterized in that the lips diverge axially from the ratchet body.

6. - The structure according to claim 1, characterized in that the lips diverge axially from the ratchet body.

7. - The structure according to claim 1, characterized in that it also comprises a mounting mechanism that connects the ratchet mechanism with the ratchet body.

8. - The structure according to claim 7, characterized in that the lips of the seal member resiliently move the separate ratchet member and ratchet body.

9. A sealed reversible ratchet structure, characterized in that it comprises: a ratchet body with a cylindrical through opening having an axis and defining a cavity, first and second annular shoulder surfaces formed in the ratchet body respectively in first and second ends of the coaxial cavity and extending parallel to a plane disposed substantially perpendicular to the axis, a ratchet mechanism mounted in the cavity, the ratchet mechanism includes a pulse member mounted for rotation relative to the ratchet body relative to the axis and having a third annular shoulder surface facing the first substantially parallel and coaxial annular shoulder surface to cooperate in order to define a first annular space therebetween, the ratchet mechanism includes an inverting member mounted for rotation with respect to the body of ratchet in relation to the shaft and having a fourth shoulder surface anu The second substantially annular and coaxial annular shoulder surface facing to cooperate in order to define a second annular space therebetween, a first seal member disposed in the first annular space and having two resilient and flexible lips extending radially and axially spaced, which respectively engage the first and third shoulder surfaces to cooperate, in order to seal the first end of the cavity and a second seal member disposed in the second annular space and having two resilient and flexible lips that are radially spaced and axially spaced, which respectively engage the second and fourth shoulder surfaces for cooperation in order to seal the second end of the cavity.

10. The ratchet structure according to claim 9, characterized in that the ratchet body has a cylindrical set of ratchet teeth defining the opening., the ratchet mechanism includes a catch mechanism mounted for ratchet engagement with the ratchet teeth.

11. Ratchet structure according to claim 9, characterized in that it further comprises a coupling structure that interconnects the pulse member and the reversing member to retain them in the ratchet body respectively in first and second ends of the cavity.

12. - Ratchet structure according to claim 11, characterized in that the first and second seal members respectively resiliently move the driving member and the reversing member axially away from the ratchet body to center the ratchet mechanism in respect of the ratchet mechanism. to the ratchet body.

13. The ratchet structure according to claim 9, characterized in that each of the first and second seal members includes an annular seal body from which the lips extend.

14. The ratchet structure according to claim 13, characterized in that in each of the first and second seal members, its lips diverge from the seal body.

15. The ratchet structure according to claim 13, characterized in that in each of the first and second seal members, its lips extend radially inwardly from the seal body.

16. The ratchet structure according to claim 15, characterized in that in each seal member the lips diverge axially from the ratchet body. The ratchet structure according to claim 9, characterized in that in each seal member the lips diverge axially from the ratchet body.