Patent Publication Number: US-11654533-B2

Title: Ratchet tools

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of and priority to U.S. patent application Ser. No. 15/156,728, filed on May 17, 2016, which is a divisional application of U.S. patent application Ser. No. 14/013,499, filed Aug. 29, 2013, of which the entire disclosures of both applications are incorporated by reference herein. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates, generally, to ratchet tools and, more particularly, to ratchet tools operable in both a powered mode and in a manual mode. 
     BACKGROUND 
     Ratchet tools are used to rotate fasteners, such as bolts and nuts, in either a clockwise or a counterclockwise direction to tighten or loosen the fasteners. Many ratchet tools include a output shaft configured to engage a fastener (e.g., via a socket removably coupled to the output shaft), a handle configured to be pivoted back-and-forth relative to the output shaft, and a ratchet mechanism coupled between the output shaft and the handle. The ratchet mechanism is generally configured to restrict rotation of the output shaft in one direction while allowing rotation of the output shaft in the opposite direction. Thus, a user pivoting the handle of a ratchet tool back-and-forth can manually drive a fastener in a single direction. Powered ratchet tools further include a motor configured to drive rotation of the output shaft when operating in a powered mode. 
     SUMMARY 
     According to one aspect, a ratchet tool may include an output shaft, a motor, and a transmission coupled between the output shaft and the motor. The transmission may include a ratchet mechanism and a speed-sensitive clutch. The speed-sensitive clutch may be configured to connect the output shaft to the motor when the motor provides rotation to the transmission above a predetermined speed so that the output shaft is driven by the motor. The speed-sensitive clutch may also be configured to disconnect the output shaft from the motor when the motor does not provide rotation to the transmission above the predetermined speed so that the output shaft is free to be rotated manually without resistance from the motor. 
     In some embodiments, the speed-sensitive clutch may be a centrifugal clutch. The speed-sensitive clutch may be coupled between the ratchet mechanism and the motor. 
     In some embodiments, the motor may include a rotor coupled to the transmission. The rotor may be configured to rotate about a motor axis. The output shaft may be configured to rotate about an output axis that is non-parallel to the motor axis. 
     In some embodiments, the ratchet tool may include a direction control coupled to the ratchet mechanism. The direction control may be configured to select a direction of ratchet mechanism engagement. The direction control may be spaced apart from the output axis. 
     In some embodiments, the ratchet tool may include a power control coupled to the motor. The power control may be configured to control rotation of the rotor. The power control may be positioned near the direction control to allow one-handed operation of both the power control and the direction control. 
     In some embodiments, the ratchet mechanism may be spaced apart from the output axis. The ratchet tool may include a direction control coupled to the ratchet mechanism and configured to select a direction of ratchet mechanism engagement. The direction control may be spaced apart from the output axis. 
     In some embodiments, the transmission may include a first bevel gear configured to rotate about a first axis parallel to the motor axis and a second bevel gear configured to rotate about a second axis parallel to the output axis. The second bevel gear may mesh with the first bevel gear. 
     According to another aspect, a ratchet tool may include a handle extending along a handle axis and housing a motor and a head coupled to the handle at a first end of the handle. The head may support an output shaft configured to be driven by the motor to rotate about an output axis. The output axis may be substantially perpendicular to the handle axis. The ratchet tool may further include a ratchet mechanism coupled between the handle and the output shaft. The ratchet mechanism may be configured to restrict rotation of the output shaft in a first direction and to allow rotation of the output shaft in a second direction opposite the first direction. The ratchet tool may further include a direction control configured to switch the first direction associated with the ratchet mechanism between a clockwise and a counterclockwise direction. The direction control may be coupled to the handle and may be spaced apart from the head along the handle axis. 
     In some embodiments, the direction control may be spaced at least one-third of a length of the handle away from the first end of the handle. The direction control may be spaced at least two-thirds of the length of the handle away from the first end of the handle. The ratchet mechanism may be spaced apart from the head along the handle axis. The ratchet mechanism may include a pawl and a toothed wheel, the toothed wheel being configured to rotate about a ratchet axis that is parallel to the handle axis. 
     In some embodiments, the ratchet tool may include a mechanical linkage coupled between the direction control and the ratchet mechanism. The mechanical linkage may extend generally parallel to the handle axis. 
     In some embodiments, the ratchet tool may further include a speed-sensitive clutch coupled between the motor and the output shaft. The speed-sensitive clutch may be configured to disconnect the output shaft from the motor when the motor does not provide rotation above a predetermined speed. The speed-sensitive clutch may be housed in the handle and may be positioned between the motor and the ratchet mechanism along the handle axis. 
     In some embodiments, the ratchet tool may further include a power control coupled to the motor. The power control may be movable between an on position in which the motor drives rotation of the output shaft and an off position in which the motor does not drive rotation of the output shaft. The direction control may be coupled to the power control and may be configured to select a direction of rotation provided by the motor when the power control is in the on position. 
     In some embodiments, the head may include an input bevel gear and an output bevel gear. The input bevel gear may be configured to rotate about the handle axis. The output bevel gear may be configured to rotate about the output axis. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The concepts described in the present disclosure are illustrated by way of example and not by way of limitation in the accompanying figures. For simplicity and clarity of illustration, elements illustrated in the figures are not necessarily drawn to scale. For example, the dimensions of some elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference labels have been repeated among the figures to indicate corresponding or analogous elements. 
         FIG.  1    is a perspective view of one illustrative embodiment of a ratchet tool operable in both a powered mode and in a manual mode; 
         FIG.  2    is a block diagram of the ratchet tool shown in  FIG.  1   ; and 
         FIG.  3    is a side elevation view of another illustrative embodiment of a ratchet tool operable in both a powered mode and in a manual mode. 
     
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
     While the concepts of the present disclosure are susceptible to various modifications and alternative forms, specific exemplary embodiments thereof have been shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that there is no intent to limit the concepts of the present disclosure to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure. 
     Referring now to  FIG.  1   , one illustrative embodiment of a ratchet tool  10  that is operable in both a powered mode and in a manual mode is shown. In the powered mode, a motor  30  included in the ratchet tool  10  drives rotation of an output shaft  16  to tighten or loosen a fastener. In the manual mode, a user may pivot the ratchet tool  10  to manually drive rotation of the output shaft  16 , thereby tightening or loosening a fastener. As described in further detail below, the ratchet tool  10  is configured such that the motor  30  does not provide resistance to the rotation of the output shaft  16  when the ratchet tool  10  is operated in the manual mode. 
     The ratchet tool  10  illustratively includes a handle  12  and a head  14  coupled to the handle  12 . The handle  12  is sized to be gripped by a user&#39;s hand and extends along a handle axis  12 A. The head  14  is coupled to a first end  21  of the handle  12  and supports the output shaft  16 , which is configured to rotate about an output axis  16 A, as shown in  FIG.  1   . The output shaft  16  is configured to be removably coupled to one of a plurality of interchangeable sockets  25  to transfer rotation of the output shaft  16  to a fastener (not shown). 
     The ratchet tool  10  also includes a power control  26  and a direction control  28 . In the illustrative embodiment of  FIG.  1   , the power control  26  and the direction control  28  are each coupled to the handle  12  near a second end  22  of the handle  12 . The power control  26  is illustratively embodied as a pivot switch that pivots relative to handle  12 , as suggested by arrow  26 P, to change the operation of the ratchet tool  10  between the manual and powered modes of operation. The direction control  28  is illustratively embodied as a rotatable ring that rotates about the handle axis  12 A, as suggested by arrow  28 R, to change the direction of rotation of the output shaft  16 , during powered and manual operation of the ratchet tool  10 , to facilitate tightening or loosening of a fastener. 
     In the powered mode of operation, a user squeezes the power control  26  to cause the motor  30  housed in the handle  12  to drive rotation of the output shaft  16 . Rotation of the output shaft  16  subsequently tightens or loosens a fastener engaged by the socket  25  coupled to the output shaft  16 . In the manual mode of operation, a user releases the power control  26  and manually pivots the handle  12  to tighten or loosen a fastener. A ratchet mechanism  24  housed in the handle  12  allows a user to pivot the handle  12  back-and-forth relative to the output shaft  16  to cause rotation of the output shaft  16  in a single direction. In the manual mode of operation, a user may be able to apply a torque through the ratchet tool  10  greater than what is provided during the powered mode of operation. Thus, the manual mode of operation might be used during final tightening or initial breaking loose of a fastener. 
     Turning now to  FIG.  2   , the ratchet tool  10  is shown to include a transmission  32  that extends through the handle  12  and into the head  14 . The motor  30  includes a rotor configured to rotate about a motor axis  30 A to provide rotation to the transmission  32 . In the illustrative embodiment, the motor axis  30 A is parallel to (and collinear with) the handle axis  12 A. The transmission  32  is configured to connect the motor  30  to the output shaft  16  when the ratchet tool  10  is in the powered mode of operation and to disconnect the motor  30  from the output shaft  16  when the ratchet tool  10  is in the manual mode of operation. 
     The motor  30  is illustratively embodied as a pneumatic motor configured to be powered by pressurized air, as suggested in  FIGS.  1  and  2   . The illustrative ratchet tool  10  includes a coupling  34  configured to removably couple the motor  30  to a source of pressurized air source, such as an air hose connected to a compressor or an air tank. In other embodiments, the motor  30  may be an electric motor and the coupling  34  may be configured to couple the motor  30  to source of electrical power (e.g., an electrical outlet or a battery). 
     The transmission  32  includes a speed-reduction gear set  36 , an angled gear set  38 , a speed-sensitive clutch  40 , and the ratchet mechanism  24 , as shown diagrammatically in  FIG.  2   . The speed-reduction gear set  36  lowers the speed of rotation provided by the motor  30  to raise the torque provided to the output shaft  16  during the powered mode of operation. The angled gear set  38  redirects rotation from the motor  30  so that the output shaft  16  is driven to rotate about the output axis  16 A. In the illustrative embodiment, the output axis  16 A is substantially perpendicular to the motor axis  30 A. The speed-sensitive clutch  40  is configured to connect the output shaft  16  to the motor  30  when the motor  30  provides rotation to the transmission  32  above a predetermined speed. The ratchet mechanism  24  is configured to allow rotation of the output shaft  16  in a single direction about the output axis  16 A. 
     In the illustrative embodiment of  FIG.  2   , the speed-reduction gear set  36  is coupled between the motor  30  and the speed-sensitive clutch  40 . When the speed-sensitive clutch  40  disconnects the motor  30  from the output shaft  16 , the speed-reduction gear set  36  is also disconnected from the output shaft  16  so that rotation of the output shaft  16  is not subject to resistance from the speed-reduction gear set  36 . The speed-reduction gear set  36  may be illustratively embodied as a planetary gear set configured to reduce the speed of rotation provided by the motor  30 . In other embodiments, the speed-reduction gear set  36  may be another speed-reduction unit (e.g., a pulley set or the like). 
     In the illustrative embodiment, the angled gear set  38  is housed in the head  14  and is coupled between the output shaft  16  and the ratchet mechanism  24 , as shown in  FIG.  2   . The angled gear set  38  redirects rotation of the rotor of the motor  30  about the motor axis  30 A to rotation of the output shaft  16  about the output axis  16 A, which is substantially perpendicular to the motor axis  30 A. The angled gear set  38  illustratively includes an input bevel gear  41  coupled to the ratchet mechanism  24  and an output bevel gear  42  coupled to the output shaft  16 . The input bevel gear  41  is configured to rotate about an input bevel axis  41 A that is parallel to (and, illustratively, co-linear with) the handle axis  12 A and the motor axis  30 A. The output bevel gear  42  is configured to rotate about an output bevel axis  42 A that is parallel to (and, illustratively, co-linear with) the output axis  16 A. 
     In the illustrative embodiment of  FIG.  2   , the speed-sensitive clutch  40  is coupled between the motor  30  and the ratchet mechanism  24 . The speed-sensitive clutch  40  is configured to connect the output shaft  16  to the motor  30  when the motor  30  provides rotation to the transmission  32  above a predetermined speed so that the output shaft  16  is driven by the motor  30  and to disconnect the output shaft  16  from the motor  30  when the motor  30  does not provide rotation to the transmission  32  above the predetermined speed so that the output shaft  16  is free to be rotated manually without resistance from the motor  30 . In the illustrative embodiment, the speed-sensitive clutch  40  is a centrifugal clutch, in which rotation of a clutch input (driven by the motor  30 ) imparts centrifugal forces on a mass. At or above a particular rotational speed, these centrifugal forces overcome an inward biasing force to drive the mass outward and into engagement with a clutch output, thereby transferring rotation through the centrifugal clutch. In other embodiments, the speed-sensitive clutch  40  may be another type of speed-sensitive unit such as an electronic clutch including a speed sensor, an actuator, and a controller. 
     The ratchet mechanism  24  is illustratively coupled between the speed-sensitive clutch  40  and the angled gear set  38 , as shown in  FIG.  2   . The ratchet mechanism  24  is housed in the handle  12  and is spaced apart from the head  14  (and, hence, from the output axis  16 A), allowing the head  14  to maintain a low profile for use in tight spaces. The ratchet mechanism  24  is configured restrict rotation of the output shaft  16  in one direction and to allow rotation of the output shaft  16  in the opposite direction. For example, the ratchet mechanism  24  may restrict rotation of the output shaft  16  in the clockwise direction while allowing rotation of the output shaft  16  in the counter-clockwise direction (or vice versa). Thus, the ratchet mechanism  24  allows a user to pivot the handle  12  back-and-forth relative to the output shaft  16  to cause rotation of the output shaft  16  in a single direction. 
     In the illustrative embodiment, the ratchet mechanism  24  includes a toothed wheel  44  and a pawl  46 , as diagrammatically shown in  FIG.  2   . The toothed wheel  44  is mounted for rotation about a wheel axis  44 A that is parallel to (and, illustratively, collinear with) the motor axis  30 A and the handle axis  12 A. The pawl  46  is movable between one position in which the pawl  46  blocks rotation of the toothed wheel  44  (and thus the output shaft  16 ) in the clockwise direction and another position in which the pawl  46  blocks rotation of the toothed wheel  44  (and thus the output shaft  16 ) in the counterclockwise direction. 
     The power control  26  is coupled to the motor  30  and configured to control operation of the motor  30  (i.e., rotation of the rotor), as suggested in  FIG.  2   . In other words, when the power control  26  is in an “on” position, the motor  30  drives rotation of the output shaft  16  and, when the power control  26  is an “off” position, the motor  30  does not drive rotation of the output shaft  16 . The power control  26  located near the second end  22  of handle  12  and is positioned near the direction control  28  to allow one-handed operation of both the power control  26  and the direction control  28  by a user. 
     In the illustrative embodiment, the direction control  28  is coupled to the power control  26  and is configured to select the direction of rotation provided by the motor  30 . For instance, in some embodiments, the direction control  28  may change the configuration of the power control  26  (e.g., reversing pneumatic couplings or electrical connections within the power control  26 ) to select the direction of rotation provided by the motor  30 . The direction control  28  is also coupled to the pawl  46  of the ratchet mechanism  24  via a mechanical linkage  48  as shown, for example, in  FIG.  2   . Via the linkage  48 , the direction control  28  is configured to move the pawl  46  between its positions to select a direction of engagement of the ratchet mechanism  24  (i.e., the direction in which the ratchet mechanism  24  restricts rotation). 
     The direction control  28  is illustratively located near the second end  22  of handle  12 , as shown in  FIGS.  1  and  2   . In particular, the direction control  28  is spaced apart from the head  14  so that the direction of ratchet mechanism  24  engagement can be changed without reaching out to the head  14  during use of the ratchet tool  10  in tight spaces. 
     Another illustrative ratchet tool  110  is shown in  FIG.  3   . The ratchet tool  110  is substantially similar to the ratchet tool  10  shown in  FIGS.  1 - 2    and described above. Accordingly, similar reference numbers (in the  100  series in  FIG.  3   ) indicate features that are similar between the ratchet tool  10  and the ratchet tool  110 . Furthermore, the description of the ratchet tool  10  (set forth above) also applies to the ratchet tool  110 , except in instances when it conflicts with the specific description below of ratchet tool  110 . 
     Unlike the ratchet tool  10 , the power control  126  of the ratchet tool  110  is illustratively embodied as a trigger, as shown in  FIG.  3   . The power control  126  pivots relative to handle  112 , as suggested by arrow  126 P, to change the operation of the ratchet tool  110  between the manual and powered modes of operation. The direction control  128  is illustratively embodied as a button that slides perpendicular to the handle axis  112 A to change the direction of rotation of the output shaft  116 , during powered and manual operation of the ratchet tool  110 . In addition, the coupling  134  of the ratchet tool  110  is configured to removably couple the motor  130  to a source of electrical power. More specifically, in the illustrative embodiment of  FIG.  3   , the coupling  134  is configured to receive a battery. 
     While certain illustrative embodiments have been described in detail in the figures and the foregoing description, such an illustration and description is to be considered as exemplary and not restrictive in character, it being understood that only illustrative embodiments have been shown and described and that all changes and modifications that come within the spirit of the disclosure are desired to be protected. There are a plurality of advantages of the present disclosure arising from the various features of the apparatus, systems, and methods described herein. It will be noted that alternative embodiments of the apparatus, systems, and methods of the present disclosure may not include all of the features described yet still benefit from at least some of the advantages of such features. Those of ordinary skill in the art may readily devise their own implementations of the apparatus, systems, and methods that incorporate one or more of the features of the present disclosure.