This Application claims priority to Chinese App. No. CN201410032786.5 filed on Jan. 24, 2014, the contents of which are incorporated by reference herein.
This disclosure relates to a ratcheting driver, and more particularly, to a bi-acting and reversible ratcheting driver.
Tools are often utilized to insert and remove fasteners. Ratcheting drivers include ratcheting mechanisms that enable drivers to apply force to the fastener when the tool is rotated in one direction, but allow the tool to rotate freely without applying a force to the fastener in the opposite direction. Movement of the ratcheting tool in the opposite direction allows the operator to reposition the tool, but otherwise rotation in this direction is wasted motion. Bi-acting drives have been developed to convert this otherwise wasted motion to positive force to the fastener. What these tools need, however, is a reversing mechanism that allows the ratcheting driver to switch directions.
Disclosed is a ratcheting driver comprising a driving mechanism combined between a handle and a working end for translating rotary motion from the handle to the working end. A switch engages the driving mechanism to switch the rotational direction of the working end between clockwise rotation and counter-clockwise rotation with an optional locked position that locks the working end. Two pairs of cooperating pawls are provided that are selectively engaged by the switch with one pawl in each of the two pairs of cooperating pawls selectively engaging one of a first ratchet gear and a second ratchet gear. Each pawl in the pair of cooperating pawls are positioned axially apart from each other in alignment with one of the first ratchet gear and the second ratchet gear.
In an embodiment, the switch comprises an upper half and a lower half. The upper half of the switch selectively engages one pawl in each of the two pairs of cooperating pawls to selectively urge one of the two pawls into engagement with the first ratchet gear. The lower half of the switch selectively engages one pawl in each of the two pairs of cooperating pawls to selectively urge one of the two pawls into engagement with the second ratchet gear. The inner circumference of the switch has one or more areas that selectively engages the pawls to move the pawls away from the first ratchet gear and the second ratchet gear.
A transmission can be provided for providing unidirectional rotation of the working end with rotation of the handle in both a clockwise direction and a counter-clockwise direction. The transmission comprises a first driving gear positioned coaxially with respect to a second driving gear. The second driving gear is fixed to the second ratchet gear. The first driving gear rotates synchronously with the first ratchet gear. A first primary transmission gear can be positioned between the first driving gear and the second driving gear for rotation about an axis that is perpendicular to the shaft for imparting rotation of the handle to rotation of the working end. A gear rack can be provided for positioning the first driving gear, the second driving gear and the primary transmission gear relative to each other.
These and other features and advantages of the present invention will be better understood by reading the following detailed description, taken together with the drawings.
Ratcheting driver 100 is reversible so that it can be selectively switched between one-way clockwise rotation and counter-clockwise rotation while still bi-acting on the work piece. Converse to the foregoing example, ratcheting driver, when its directional switch has been moved to counter-clockwise rotation, ratcheting driver 100 operates to translate counter-clockwise rotation of the handle (working direction) to counter-clockwise rotation of the working end (working direction) followed by clockwise rotation of the handle (repositioning direction) with continued counter-clockwise rotation of the working end (working direction).
Ratcheting driver 100 includes a handle 102 combined via a driving mechanism 104 (see
A transmission 112 is sleeved onto shaft 114.
First primary transmission gear 124 and second primary transmission gear 126 are spaced apart from each other by a gear rack 128 that holds first primary transmission gear 124 and second primary transmission gear 126. Gear rack 128 has a first hub 130 for first primary transmission gear 124 and a second hub 132 for second primary transmission gear 126. First hub 130 and second hub 132 define a second axis defined by fasteners 134 that hold first hub 130 and second hub 132 to gear rack 128 that is perpendicular to a first axis defined by shaft 114. Shaft 114 is sleeved into and extends coaxially with first driving gear 120 and second driving gear 122 and is secured to first driving gear 120 to rotate therewith, while second driving gear 122 rotates freely with respect to shaft 114.
The operation of transmission 112 is better understood in the context of the operation of a reversing mechanism 140 that engages transmission 112 to convert bidirectional rotation of handle 102 to unidirectional rotation of working end 106 and switch rotational direction of working end 106.
In this regard, clockwise rotation of first ratchet gear 141 cause clockwise rotation of shaft 114 and a corresponding clockwise rotation of first driving gear 120 and working end 106. The clockwise rotation of first driving gear 120 translates through first primary transmission gear 124 and second primary transmission gear 126 to counter-clockwise rotation of second driving gear 122 and second ratcheting gear 143. Similarly, clockwise rotation of second ratchet gear 143 causes clockwise rotation of second driving gear 122. The clockwise rotation of second driving gear 122 translates through first primary transmission gear 124 and second primary transmission gear 126 to counter-clockwise rotation of first driving gear 120 and first ratcheting gear 141.
Reversing mechanism 140 restricts the rotation of working end 106 to a single direction. Reversing mechanism 140 includes two pairs of cooperating pawls 142, 144 and 146,148. Each pawl 142, 144, 146, and 148 in the pair of cooperating pawls 142, 144 and 146,148 are positioned axially apart from each other to engage one of first ratchet gear 141 and second ratchet gear 143 to provide selective one-way rotation of working end 106. A pawl cage 150 is provided with at least four openings 152, 154, 156, and 158 to receive one of pawls 142, 144, 146, and 148, respectively. Pawls 142 and 144 are positioned in openings 152 and 154, respectively, which are spaced on opposite sides from each other in pawl cage 150 and coaxially from each other to selectively engage first ratchet gear 141 and second ratchet gear 143, respectively. Similarly, pawls 146 and 148 are positioned in openings 156 and 158, respectively, which are spaced on opposite sides from each other of pawl cage 150 and coaxially from each other to selectively engage first ratchet gear 141 and second ratchet gear 143, respectively.
Pawls 142, 144, 146, and 148 are biased in their respective openings 152, 154, 156, and 158 by springs 160 and engage their corresponding first ratchet gear 141 and second ratchet gear 143 according to their position by switch 108. Switch 108 is effectively divided into an upper half 109 and a lower half 111 that corresponds with the first ratchet gear 141 and second ratchet gear 143, respectively, and acts upon pawls 142, 146 and pawls 144, 148, respectively. A ball 166 biased outward from pawl cage 150 by a spring 168 engages one of three detents 162, 163, and 164 (shown clearly in
In other embodiments, the relative position of the pawls 142, 144, 146, and 148 with respect to first ratchet gear 141 and second ratchet gear 143 can be switched. While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it should be understood by those of ordinary skill in the art that various changes, substitutions and alterations can be made herein without departing from the scope of the invention as defined by appended claims and their equivalents.
Number | Date | Country | Kind |
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201410032786.5 | Jan 2014 | CN | national |