Motor-driven rebar cutter

Abstract

A power tool comprising a housing defining a longitudinal axis, a motor having a motor output shaft, a gear housing, and a blade guard partially receiving a rotating blade. The power rebar cutter includes a gear train at least partially housed within the gear housing and configured to transmit torque from the motor output shaft to a blade, and includes a shaft and a single intermediate shaft that transmits torque from the motor output shaft to the shaft. The gear train includes a pinion gear coupled for common rotation with the motor output shaft and a ring gear coupled for common rotation with the intermediate shaft and meshing with the pinion gear. The ring gear is located between a first plane defined by the blade and a parallel second plane containing a rotational axis of the motor output shaft.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Patent Application No. 63 / 707,572, filed October 15, 2024, U.S. Provisional Patent Application No. 63 / 631,827, filed April 9, 2024, and U.S. Provisional Patent Application No. 63 / 622,950, filed January 19, 2024, the entire contents of which are incorporated herein by reference. FIELD OF THE INVENTION

[0002] The present invention relates to cordless motor-driven tools, in particular motor-driven rebar cutters. BACKGROUND OF THE INVENTION

[0003] Motor-driven rebar cutters use a cutting blade to cut a workpiece, such as rebar. SUMMARY OF THE INVENTION

[0004] The present invention, in one aspect, provides a power tool comprising a housing defining a longitudinal axis, a motor housed in the housing having a motor output shaft, a gear housing coupled to the housing, and a blade guard coupled to the gear housing and at least partially housing a rotating blade. The power rebar cutter includes a gear train at least partially housed in the gear housing and configured to transmit torque from the motor output shaft to the blade. The gear train includes an arbor to which the blade is coupled for common rotation, and a single intermediate shaft disposed between the motor output shaft and the spindle. The intermediate shaft is configured to transmit torque from the motor output shaft to the shaft.The gear train includes a pinion gear coupled for common rotation with the engine output shaft, and a ring gear coupled for common rotation with the intermediate shaft and meshing with the pinion gear. The ring gear is disposed between a first plane defined by the blade and a parallel second plane containing a rotational axis of the engine output shaft.

[0005] The present invention provides, in another aspect, a motor-driven rebar cutter including a housing having a longitudinal axis, a motor received within the housing, a gear housing coupled to the housing, a blade guard coupled to the gear housing, the blade guard having an opening extending in a direction of the longitudinal axis into which rebar is received by a blade during a cutting operation, a gear train at least partially received within the gear housing and configured to transfer torque from the motor to the blade, and a lighting assembly configured to project light onto the opening to illuminate a portion of the blade exposed through the opening in the blade guard.

[0006] The present invention, in another aspect, provides a motor-driven rebar cutter comprising a housing defining a longitudinal axis, a motor housed in the housing, a gear housing coupled to the housing, a blade guard coupled to the gear housing, the blade guard including an opening extending in a direction of the longitudinal axis into which rebar is received by a blade during a cutting operation, a gear train at least partially housed in the gear housing and configured to transmit torque from the motor to the blade, the gear train including a spindle to which the blade is attached, and a blade cover pivotally connected to the blade guard between a closed position in which the blade guard and the blade cover together define a chamber,in which the blade is rotatable, and an open position in which the spindle is accessible for removing the blade.

[0007] The present invention, in another aspect, provides a motor-driven rebar cutter comprising a housing defining a longitudinal axis, a motor housed in the housing, a gear housing coupled to the housing, a blade guard coupled to the gear housing, the blade guard including an opening extending in a direction of the longitudinal axis into which rebar is received by a blade during a cutting operation, a gear train at least partially housed in the gear housing and configured to transmit torque from the motor to the blade, the gear train including a spindle to which the blade is attached, and a dust chute at least partially defined by the blade guard and aligned along a central axis,which is oriented obliquely relative to the longitudinal axis of the housing.

[0008] The present invention, in another aspect, provides a power tool having a housing defining a longitudinal axis, a motor received within the housing, a gear housing coupled to the housing, a blade having an opening, a blade guard coupled to the gear housing in which the blade is at least partially received, and a gear train at least partially received within the gear housing. The gear train is configured to transfer torque from the motor to the blade. The gear train includes a spindle with a bottom recess defining a diameter. The power rebar cutter includes a locking flange and a fastener. The fastener is configured to couple the locking flange to the spindle such that the blade is clamped between the spindle and the locking flange.The locking flange includes a first cylindrical portion configured to be received in the lower recess of the spindle and a second cylindrical portion defining a second diameter greater than the first diameter of the lower recess. The second cylindrical portion is received in the opening of the blade. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a top perspective view of a motor-driven rebar cutter. Fig. 2 is a perspective view of the motor-driven rebar cutter of Fig. 1 from the bottom. Fig. 3 is a cross-sectional view of the motor-driven rebar cutter of Fig. 1, which runs along section 3-3 in Fig. 1 is recorded. Fig. 4 is an enlarged view of a gear train of the motor-driven rebar cutter of Fig. 3. Fig. 5 is a plan view of the motor-driven rebar cutter of Fig. 1. Fig. 6 is an enlarged front view of the motor-driven rebar cutter of Fig. 1, which shows a lighting arrangement. Fig. Figure 7 is an enlarged view of the lighting assembly of the motor-driven rebar cutter of Fig. 6 with the gearbox cover removed. Fig. Figure 8A is an enlarged front view of another embodiment of a motor-driven rebar cutter showing another lighting arrangement. Fig. Figure 8B is a plan view of the lighting assembly of the motor-driven rebar cutter of Fig. 8A with gearbox cover removed. Fig. 9 is an enlarged front perspective view of another embodiment of a motor-driven rebar cutter showing a lighting assembly. Fig. 10 is a perspective view of the bottom of the motor-driven rebar cutter of Fig. 9 with parts removed. Fig. 11 is an enlarged perspective view of another embodiment of the power rebar cutter showing onboard storage of a hex wrench. Fig. 12 is a top perspective view of another embodiment of a motor-driven rebar cutter. Fig. 13 is an enlarged perspective view of the motor-driven rebar cutter of Fig. 12, which illustrates a battery holder. Fig. 14 is a cross-sectional view of the motor-driven rebar cutter of Fig. 12, taken along section 14-14 in Fig. 12. Fig. 15 is an enlarged view of the spindle of the motor-driven rebar cutter of Fig. 14. Fig. 16 is an enlarged view of another embodiment of a cutting blade for use with the motor-driven rebar cutter of Fig. 12.

[0009] Before explaining embodiments of the invention in detail, it should be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is also capable of other embodiments and may be practiced or carried out in various ways. DETAILED DESCRIPTION

[0010] Fig. 1 shows a power tool 10 (i.e., a power rebar cutter) having a housing 14 with a first end 16 having a battery receptacle 17 configured to receive a battery pack 18, and a second end 22 connected to a gear housing 26. The housing 14 defines a longitudinal axis L that also extends through the gear housing 26 ( Fig. 3). The housing 14 includes a handle 34 which is designed to be grasped by a user (see also Fig. 1). In some embodiments, the handle 34 is constructed of a different material than the housing 14 to optimize the user's grip. In the illustrated embodiment of the power-driven rebar cutter 10, the handle 34 is constructed of a thermoplastic elastomer that is molded onto the housing 14. The housing 14 includes a trigger (e.g., a paddle 38) configured to be actuated by the user to activate the power-driven rebar cutter 10. The paddle 38 includes a locking lever 42 pivotally connected to the paddle 38 ( Fig. 3). To successfully operate the paddle 38, the user must first turn the locking lever 42 counterclockwise with respect to the reference frame of Fig. 3 until the locking lever 42 is received in a recess 44 in the paddle 38.

[0011] In some embodiments, the battery pack 18 may be an 18-volt rechargeable battery pack for power tools. The battery pack 18 may include multiple battery cells having, for example, a lithium (Li), lithium-ion (Li-ion), or other lithium-based chemistry. The battery cells may have, for example, a lithium cobalt (Li-Co), lithium manganese (Li-Mn) spinel, or Li-Mn nickel chemistry. In such embodiments, each battery cell may have a nominal voltage of, for example, 3.6 V, 4.0 V, or 4.2 V. In other embodiments, the battery cells may have a nickel-cadmium, nickel-metal hydride, or lead-acid battery chemistry. In further embodiments, the battery pack 18 may include fewer or more battery cells, and / or the battery cells may have different nominal voltages.In another embodiment, the battery pack 18 may be a dedicated battery housed (partially or entirely) within the power rebar cutter 10. The battery pack 18 may also be configured for use with other cordless power tools such as drills, screwdrivers, grinders, wrenches, and saws.

[0012] With reference to Fig. 1, the gear housing 26 is connected to the second end 22 of the housing 14 by a first pair of fasteners 52 and a second pair of fasteners 54. The gear housing 26 receives an auxiliary handle 58 via a threaded opening (not shown) in the gear housing 26. In some embodiments, the user can remove the auxiliary handle 58 from the power rebar cutter 10 and use the power rebar cutter 10 without the auxiliary handle 58. In some embodiments, the user can reposition the auxiliary handle 58 on the cutter, for example, at a second threaded opening 60 in the gear housing 26. As shown in Fig. 5, the second threaded opening 60 is perpendicular to the threaded opening which holds the auxiliary handle 58 in the position shown in Fig. 1 shown position. A third threaded opening 62 can be formed in the gear housing 26 on an opposite side of a plane M ( Fig. 5). The plane M bisects the second threaded opening 60 and contains the longitudinal axis L. In some embodiments, the auxiliary handle 58 may include a sensor (e.g., a capacitive sensor, not shown) to detect the presence of the user's hand on the auxiliary handle 58, thereby enabling activation of the motor-driven rebar cutter 10 only when the user grasps the auxiliary handle 58. A gear housing cover 64 ( Fig. 1) is connected to the transmission housing 26 via the first pair of fasteners 52 and a third pair of fasteners 66.

[0013] With further reference to Fig. 1, the power-driven rebar cutter 10 includes a blade guard 70 coupled to the gear housing 26 by the third pair of fasteners 66. The blade guard 70 includes a gap or opening 72 (e.g., a front opening) into which rebar is received. In the illustrated construction, the opening 72 is located on a side of the blade guard 70 opposite the side of the blade guard 70 connected to the housing 14. In other constructions, the opening 72 is located on a side of the blade guard 70 opposite a side having the pair of fasteners 66. The front opening 72 extends in the direction of the longitudinal axis L. A guide block 78 is coupled to the blade guard 70 by fasteners 82. The guide block 78 is U-shaped and includes a projection 84.The projection 84 is configured to position the front opening 72 of the power-driven rebar cutter 10 around a workpiece, such as a piece of rebar. The guide block 78 supports a front range adjuster 88 adjacent the front opening 72 having a fastener 90. The front range adjuster 88 includes a horizontal slot 92 that serves to receive the fastener 90. In order for the user to secure the front range adjuster 88, the fastener 90 must be tightened to clamp the front range adjuster 88 to the guide block 78. The front range adjuster 88 can be adjusted along the length of the horizontal slot 92 to increase or decrease the front opening 72, thereby limiting the effective width of the front opening 72.To decrease the effective width of the front opening 72, the user slides one side 94 of the front range adjuster 88 toward the projection 84. To increase the effective width of the front opening 72, the user slides the side 94 away from the projection 84.

[0014] With reference to the Fig. 1 and Fig. 2, the motor-driven rebar cutter 10 includes a blade cover 98 pivotally connected to the blade guard 70 via a pair of joints 102. As shown in Fig. 2, the blade cover 98 substantially replicates the outer profile of the blade guard 70. Indeed, the blade cover 98 includes an opening 106 that mimics the shape of the front opening 72 of the blade guard 70. Indeed, the opening 106 of the blade cover 98 partially defines the front opening 72. The blade cover 98 includes a pair of threaded openings 110 for receiving blade cover fasteners 114 that extend through the blade guard 70 and engage the blade cover 98 to hold it in a closed position. In the illustrated embodiment, the blade cover fasteners 114 are a combination fastener (e.g., a combination wing screw and hex head). In other embodiments, the blade cover fasteners 114 may be solely a wing screw or a hex head screw.To allow the user to access the cutting blade 118 of the power rebar cutter 10, the blade cover fasteners 114 are unscrewed from the threaded openings 110, allowing the blade cover 98 to pivot freely about the hinges 102 defining an axis H. The axis H is parallel to the auxiliary handle 58. In other embodiments, the hinges 102 may be oriented to run parallel to the blade cover fasteners 114. When the hinges 102 are oriented parallel to the blade cover fasteners 114, the blade cover 98 would rotate clockwise and counterclockwise when viewed from the top of the gear housing 26. To secure the blade cover 98, the user positions the blade cover 98 flush with the blade guard 70 so that the blade cover fasteners 114 are screwed into the threaded openings 110.Accordingly, the blade cover 98 is pivotable between a closed position in which the blade cover 98 and the blade guard 70 together form a chamber in which the cutting blade 118 is rotatable, and an open position in which the blade cover 98 is disengaged from the blade guard 70 (i.e., the blade cover fasteners 114 are removed from the threaded openings 110) so that the blade cover 98 can be pivoted away from the blade guard 70, exposing the cutting blade 118 for removal and / or replacement.

[0015] The Fig. 3 and Fig. 4 illustrate the motor-driven rebar cutter 10, which includes a motor 122 housed within the housing 14. The motor 122 includes a stator 126 secured to the housing 14 and a rotor 130 rotatably supported within the housing 14. The motor 122 includes a motor output shaft 134 coupled via a pair of bearings 138a, 138b for common rotation with the rotor 130 about a rotational axis R of the motor output shaft 134. In the illustrated embodiment, the rotational axis R and the longitudinal axis L are coaxial. The bearing 138a is supported by the housing 14, while the bearing 138b is supported by the gear housing 26.

[0016] Fig. 3 and Fig. 4 show a gear train 142 partially housed within the gear housing 26 and configured to transmit torque from the motor 122 to the cutting blade 118. The cutting blade 118 defines a plane B ( Fig. 4 and Fig. 14). The gear train 142 includes a pinion 144 connected to the front end of the motor output shaft 134 and extending beyond the bearing 138b. The pinion 144 is connected to the motor output shaft 134 via a left-hand thread arrangement and is coupled for common rotation with the motor output shaft 134. The motor output shaft 134 and the pinion 144 are referenced in a frame ( Fig. 4) rotated clockwise (CW) along the rotational axis R of the motor output shaft 134 as viewed from the front of the motor-driven rebar cutter 10. A plane S contains the rotational axis R and is parallel to plane B. The gear train 142 also includes an intermediate bevel gear (i.e., a ring gear 146) that meshes with the pinion gear 144. The ring gear 146 is located between plane B and the parallel plane S. The intermediate gear 146 is coupled for common rotation to a single intermediate shaft 150. The intermediate shaft 150 is aligned perpendicular to the motor output shaft 134. Because the intermediate shaft 150 is coupled for common rotation to the intermediate ring gear 146, the pinion gear 144 drives the intermediate shaft 150. The intermediate shaft 150 is rotatably supported by a pair of intermediate shaft bearings 154a, 154b.A first intermediate shaft bearing 154a is received in a pocket in the gear housing 26, and a second intermediate shaft bearing 154b is received in a pocket in the blade guard 70. The intermediate shaft 150 includes a drive gear 158 coupled to the intermediate shaft 150 for common rotation. The drive gear 158 meshes with a driven gear 162 coupled to a spindle 166 for common rotation. The drive gear 158 is located between plane B and the ring gear 146. The spindle 166 is aligned parallel to the intermediate shaft 150. The spindle 166 is rotatably supported by a pair of spindle bearings 170a, 170b. A first spindle bearing 170a is received in a pocket in the gear housing 26, and a second intermediate shaft bearing 154b is received in a pocket in the blade guard 70.The cutting blade 118 is coupled for common rotation with the spindle 166 and is axially secured to the spindle 166 by a locking flange 178, which in turn is clamped to the spindle 166 by a fastener 182. The spindle 166 is supported by a reference frame (. Fig. 4) is rotated clockwise (CW) along a rotational axis A of the spindle 166 when viewed from a top side of the gear housing 26. An end surface of the motor output shaft 134 defines a plane E ( Fig. 4 and Fig. 14). The distance D1 between the plane E and the rotational axis A of the spindle 166 is between 40 millimeters and 50 millimeters. In the illustrated embodiment, the distance D1 is 46 millimeters.

[0017] The motor-driven rebar cutter 10 includes a locking pin 183 biased in a first direction by a spring 184. The locking pin 183 is received on a top surface of the gear housing 26 that is angled relative to plane B. The locking pin 183 includes a stop member 185 configured to be biased by the user in a second direction such that the locking pin 183 is received in a recess or hole (not shown) in the intermediate ring gear 146. Engagement of the locking pin 183 in the recess or hole of the intermediate ring gear 146 prevents rotation of the intermediate ring gear 146 and thus the gear train 142.In other words, the engagement of the locking pin 183 with the intermediate ring gear 146 makes the intermediate ring gear 146 and thus the entire gear train 142 non-rotatable.

[0018] In order for the user to remove the cutting blade 118, the blade cover 98 must be in the open position. Specifically, the blade cover fasteners 114 must be released from the threaded openings 110 so that the blade cover 98 pivots about the hinges 102 to expose the fastener 182 connected to the spindle 166. To remove the cutting blade 118, the fastener 182 must be removed so that the locking flange 178 releases the cutting blade 118. The user can push the locking pin 183 over the stop member 185 in the second direction so that the locking pin 183 engages the intermediate ring gear 146 and non-rotatably locks it so that the spindle 166 does not rotate when the fastener 182 is released from the spindle 166.The locking flange 178 releases its clamping force on the cutting blade 118 when the fastener 182 is released from the spindle 166, allowing the user to remove the cutting blade 118. The cutting blade 118 has a diameter between 125 millimeters and 140 millimeters. In the illustrated embodiment, the diameter is 137 millimeters.

[0019] Similarly, the blade cover 98 must be in the open position to allow the user to attach the cutting blade 118. The user can push the locking pin 183 over the stop member 185 in the second direction to cause the locking pin 183 to engage and rotationally lock the intermediate ring gear 146 so that the spindle 166 does not rotate when the fastener 182 is tightened to the spindle 166 with the locking flange 178 therebetween. The locking flange 178 engages the cutting blade 118 so that it is flush with a surface of the spindle 166 when the fastener 182 is fully tightened. The user can return the blade cover 98 to the closed position to allow the blade cover fasteners 114 to re-engage the threaded openings 110.

[0020] In order for the user to activate the motor-driven rebar cutter 10 to perform a cutting operation on a workpiece (e.g., a piece of rebar), the user must pivot the locking lever 42 counterclockwise so that the locking lever 42 is received in the recess 44 of the paddle 38 and press the paddle switch 38 against a biasing member (e.g., a spring 200) disposed between the housing 14 and the paddle 38. When the paddle 38 pivots about a pivot 204 toward the housing 14, an electrical switch (not shown) is actuated to activate the motor 122 with electrical power from the battery pack 18. The rotation of the motor output shaft 134 is transmitted via the pinion gear 144 to the intermediate ring gear 146. The rotation of the intermediate ring gear 146 is transmitted to the driven gear 162 via the intermediate shaft 150 and the drive gear 158.The spindle 166 rotates in unison with the driven gear 162, thereby transmitting torque to the cutting blade 118 to rotate it. The motor-driven rebar cutter 10 includes a controller configured to control the deceleration of the motor-driven rebar cutter 10 by monitoring the phase voltage of the motor 122, as described at least in U.S. Patent No. 11,557,989, the entire contents of which are incorporated herein by reference. The motor-driven rebar cutter 10 includes a brake or stop switch 206 that signals the controller to initiate braking. Additionally, the motor-driven rebar cutter 10 includes a cut stop function to detect when the motor-driven rebar cutter 10 is cutting through a workpiece, as described at least in U.S. Patent No. 10,562,116, the entire contents of which are incorporated herein by reference.

[0021] Fig. Figure 5 shows the power-driven rebar cutter 10, which includes a dust chute 208. The dust chute 208 is defined by the blade guard 70 and the blade cover 98 when in the closed position and extends along a central axis C. The central axis C is oriented obliquely with respect to the plane M and the longitudinal axis L. The dust chute 208 is also oriented tangentially to the cutting blade 118 so that dust and debris are discharged from the power-driven rebar cutter 10 and away from the user. In the embodiment shown, the dust chute 208 is angled to successfully capture dust and debris when the cutting blade 118 rotates clockwise (CW) relative to the frame of reference of Fig. 5. In other embodiments, the cutting blade 118 rotates counterclockwise so that the dust chute would be on the opposite side of plane M. The dust chute 208 includes a rib 212 at one end of the dust chute 208 and an adjacent notch 216. The power rebar cutter 10 further includes a removable debris receptacle 218 selectively connected to the rib 212 and the notch 216, with a retaining clip (not shown) received in the notch 216. In some embodiments, the removable debris receptacle 218 is a chip bag.

[0022] Fig. 6 shows the motor-driven rebar cutter 10, which includes a lighting assembly 220 connected to a front end 222 of the motor-driven rebar cutter 10. In particular, the lighting assembly 220 is disposed on the gear housing 26. The lighting assembly 220 includes a lens 224 configured to direct light onto a portion of the cutting blade 118 exposed through the front opening 72. The lens 224 is disposed between the gear housing 26 and the gear housing cover 64 and is located near the front opening 72. More specifically, the lens 224 is disposed symmetrically about the plane M that bisects the gear housing 26. In some embodiments, the lens 224 is made of polycarbonate. The lighting assembly 220 also includes a light source (e.g., a light-emitting diode or "LED" 228; Fig. 8B) disposed on the gear housing 26. When activated, the LED 228 illuminates the portion of the cutting blade 118 visible through the front opening 72. The LED 228 receives electrical power from wires (not shown) routed through and / or around the gear housing 26. The gear housing 26 includes a notch 230 through which the light from the LED 228 can pass to reach the front opening 72.

[0023] Fig. Figure 7 shows the motor-driven rebar cutter 10 with the gear housing cover 64 removed. In some embodiments, the electrical wires connected to the LED 228 are routed around the outside of the gear housing 26 and through an opening 232 in the gear housing 26, around the motor 122, and to a circuit board assembly (not shown). In some embodiments, the LED 228 is activated when the user presses the paddle 38.

[0024] Fig. 8A and Fig. 8B illustrate a lighting assembly 300 for use with another embodiment of a power-driven rebar cutter 304, wherein the same features as in the power-driven rebar cutter 10 are identified by the same reference numerals. The power-driven rebar cutter 304 includes a gear housing 308 and a blade guard 312. The gear housing 308 and the blade guard 312 define a projection 316 including an angled surface 320 angled toward the portion of the cutting blade 118 exposed through the front opening 72. The lighting assembly 300 includes the lens 224 and the LED 228. The lighting assembly 300 further includes a second lens 324 disposed on the angled surface 320 and an LED 328 disposed behind the lens 324.The LED 328 also illuminates the portion of the cutting blade 118 exposed through the front opening 72; however, shadows that would otherwise be caused by a piece of reinforcing steel positioned in the front opening 72 that blocks the light emitted by the LED 228 are avoided by the additional light emitted by the LED 328.

[0025] Because the LED 328 is disposed between the gear housing 308 and the blade guard 312, electrical wires for supplying electrical power to the LED 328 are routed through a chamber defined between the gear housing 308 and the blade guard 312. In some embodiments, the gear housing 308 includes a conduit (not shown) that allows a wire to be routed to the chamber defined between the gear housing 308 and the blade guard 312 and to supply power to the LED 328.

[0026] Fig. 9 shows a lighting assembly 400 for use with another embodiment of a motor-driven rebar cutter 404, wherein the same features as in the motor-driven rebar cutter 10 are identified by the same reference numerals. The motor-driven rebar cutter 404 includes a gear housing 408 and a blade guard 412 defining a projection 416 including an angled surface 420 angled toward the portion of the cutting blade 118 exposed through the front opening 72. The lighting assembly 400 includes a lens 424 disposed on the angled surface 420. A light source (e.g., an LED 428) is disposed behind the lens 424 and directs the light emitted by the LED 428 onto the portion of the cutting blade 118 exposed through the front opening 72.When activated, the LED 428 illuminates the portion of the cutting blade 118 exposed through the front opening 72. The LED 428 receives electrical power from electrical wires (not shown) routed through and / or around the gear housing 408. In the embodiment shown in . Fig. In the embodiment shown in Figure 10, the gear housing 408 includes an opening 432 through which the electrical wires are passed. Fig. Figure 10 shows the power-driven rebar cutter 404 with the blade guard 412 removed to illustrate the opening 432 leading into the interior of the housing 14 and a channel 434 within the gear housing 408 that extends between the opening 432 and the front end of the gear housing 408, where the LED 428 is located. The electrical wires run between the LED 428 and the opening 432 and are embedded in the channel 434. When the blade guard 412 is attached to the gear housing 408, the electrical wires are retained in the channel 434.

[0027] Fig. 11 illustrates another embodiment of a motor-driven rebar cutter 500 that includes integrated storage for a hex wrench 504. The motor-driven rebar cutter 500 includes a housing 508 having a first end 512 proximate the battery pack (not shown). The first end 512 includes a pair of receptacles 516 configured to receive the hex wrench 504, for example, with a snap-in connection. The hex wrench 504 can be removed from the receptacles 516 and used to remove the cutting blade 118 from the spindle 166, as described above.

[0028] Fig. 12 shows another embodiment of a power rebar cutter 600, wherein the same features as in power rebar cutter 10 are identified by the same reference numerals. Power rebar cutter 600 is similar to power rebar cutter 10, and therefore only the differences will be discussed. Power rebar cutter 600 includes a gear housing 604 and a blade guard 608. Dust chute 208 of blade guard 608 includes rib 212, notch 216, and a bulge 610. Power rebar cutter 600 includes an LED (not shown) located at a front end 222 of power rebar cutter 600.

[0029] Fig. 13 shows the battery holder 17 of the motor-driven rebar cutter 600. The battery holder 17 includes a tethering hook 612.

[0030] The tether hook 612 is configured for anchoring a tether strap (not shown). In the illustrated embodiment, the tether hook 612 is flanked by recesses 616 of the battery receptacle 17. The recesses 616 are connected to one another so that the tether strap can loop around the tether hook 612. In other embodiments, the tether hook 612 stands freely on the battery receptacle 17 (e.g., without the recesses 616). The battery receptacle 17 of the motor-driven rebar cutter 600 additionally includes a tool storage container 620 configured to receive a tool (e.g., the hex wrench 504) for removing the cutting blade 118 from the spindle 166. The tool storage container 620 includes a first recess 624 extending transversely into the battery receptacle 17 and a second recess 628 extending longitudinally along one side of the battery receptacle 17.The second recess 628 includes a protrusion 632 configured to hold the hex wrench 504 in position. Adjacent to the second recess 628 is a third recess 636. The third recess 636 is configured to provide an area for a user to grasp the hex wrench 504 to remove it from the tool storage container 620.

[0031] As in Fig. 14, the only difference in the gear train 142 of the power rebar cutter 600 is that the gear train 142 is housed in a differently shaped gear housing 604. A first intersection point X is defined at an intersection of the rotational axis A of the spindle 166 and the top of the gear housing 604, which defines a plane G. A second intersection point Y is defined at an intersection of the rotational axis A of the spindle 166 and a bottom of the blade cover 98. The distance D2 between the first intersection point X and the second point Y is between 70 millimeters and 80 millimeters. In the illustrated embodiment, the distance D2 is 72 millimeters. The plane G is oriented at an angle α between 20 and 25 degrees relative to the plane B. In the illustrated embodiment, the angle α is equal to 22 degrees.

[0032] Fig. 15 shows the spindle 166, which has an upper recess 640 and an adjacent lower recess 644. The upper recess 640 is adjacent to a threaded opening 648 that receives the fastener 182 for clamping the locking flange 178 to the spindle 166. The upper recess 640 defines an inner diameter Θ1 and the lower recess 644 defines a larger inner diameter Θ2. In the illustrated embodiment, the diameter Θ1 is between 16 millimeters and 20 millimeters. More specifically, in the illustrated embodiment, the diameter Θ1 is 18.4 millimeters. In the illustrated embodiment, the diameter Θ2 is between 25 millimeters and 30 millimeters. More specifically, in the illustrated embodiment, the diameter Θ2 is 27.6 millimeters. The lower recess 644 is adjacent to a lower surface 652 of the spindle 166 which contacts the blade 118.

[0033] The locking flange 178 includes an upper cylindrical portion 656 received in the upper recess 640, a middle cylindrical portion 660 received in the lower recess 644, a lower cylindrical portion 664 adjacent to the middle cylindrical portion 660, and a flange 668 adjacent to the lower cylindrical portion 664. The upper cylindrical portion 656 has a diameter Θ3 such that the upper cylindrical portion 656 is received in the upper recess 640. In other words, the diameter Θ3 is nominally smaller than the diameter Θ1. The upper cylindrical portion 656 includes a chamfer 672. The middle cylindrical portion 660 has a diameter Θ4 such that the middle cylindrical portion 660 is received in the adjacent lower recess 644. In other words, the diameter Θ4 is nominally smaller than the diameter Θ2.The middle cylindrical portion 660 includes a chamfer 676. The lower cylindrical portion 664 has a diameter Θ5 that is larger than the diameter Θ2 (. Fig. 14). Thus, the lower cylindrical portion 664 is not received in the lower recess 644 (i.e., the lower cylindrical portion 664 does not axially overlap with the lower recess 644 along the rotational axis A of the spindle 166). In the illustrated embodiment, the diameter Θ5 is between 25 millimeters and 30 millimeters. More specifically, in the illustrated embodiment, the diameter Θ5 is 28 millimeters. The lower cylindrical portion 664 includes a chamfer 680. The chamfer 680 transitions between the central cylindrical portion 660 and the lower cylindrical portion 664 (i.e., from diameter Θ4 to diameter Θ5). In some constructions, the locking flange 178 does not include the chamfer 680. In other words, the transition between the central cylindrical portion 660 and the lower cylindrical portion 664 is a step.

[0034] The diameter Θ5 is nominally smaller than an inner diameter Θ6 of a blade opening 684 of the blade 118 such that the lower cylindrical portion 664 is received within the blade opening 684. In the illustrated embodiments, the difference between the diameter Θ2 and the diameter Θ5 is approximately 0.4 millimeters. The lower cylindrical portion 664 includes an axial distance D3 defined along the rotational axis A from the central cylindrical portion 660 to the flange 668. The axial distance D3 is less than the thickness T1 of the blade 118. In the illustrated embodiment, the thickness T1 is 1.2 millimeters. In other embodiments, the thickness T1 is greater than 1.2 millimeters or less than 1.2 millimeters.

[0035] The flange 668 includes a chamfer 688 extending from an inner edge 692 to an outer edge 696. In the illustrated embodiment, the inner edge 692 is disposed radially proximal to the rotational axis A of the spindle 166 relative to the outer edge 696. Furthermore, the inner edge 692 is disposed relative to the outer edge 696 axially proximal to the bottom surface 652 along the rotational axis A of the spindle 166. The inner and outer edges 692, 696 are disposed radially outward of the lower recess 644 relative to the rotational axis A. The blade 118 includes a corresponding chamfer 700 configured to engage the flange 668 (more specifically, the chamfer 688) such that the blade 118 is disposed between the spindle 166 and the locking flange 178. The bevel 700 is located next to the blade opening 684.

[0036] The locking flange 178 is configured to clamp the blade 118 axially along a direction parallel to the rotational axis A of the spindle 166. The diameter Θ6 of the blade opening 684 is larger than the diameter Θ2 of the lower recess 644, so that the axial clamping force from the locking flange 178 is directed radially outward from the lower recess 644 relative to the rotational axis A. Thus, the blade 118 is fully supported on the bottom surface 652 because the diameter Θ2 of the lower recess 644 is smaller than the diameter Θ6 of the blade opening 684.

[0037] The blade 118 experiences less deflection due to the clamping of the locking flange 178 onto the spindle 166 when the blade 118 fully rests on the bottom surface 652. For example, in a design where the diameter Θ6 of the blade opening 684 is smaller than the diameter Θ2 of the lower recess, an axial force of the locking flange 178 is not fully supported on the bottom surface 652. In other words, the blade opening 684 is positioned radially inward of the lower recess 644 relative to the rotation axis A. As such, the blade opening 684 is not axially supported by the bottom surface 652, potentially causing the inner periphery of the blade 118 to deflect upward in a direction parallel to the rotational axis A, which in turn would cause an outer periphery 704 of the blade 118 to deflect downward or "pinch."In some designs, the outer periphery 704 of the blade 118 could be deflected by more than 1 millimeter in a direction parallel to the rotational axis A. In the illustrated design with the blade opening 684 supported by the bottom surface 652, the displacement of an outer periphery of the blade 118 is less than 0.25 millimeters.

[0038] Fig.Figure 16 shows another embodiment of a cutting blade 800 that is interchangeable with the cutting blade 118. In other words, the cutting blade 800 is compatible with the power-driven rebar cutters 10, 600. The blade 800 is very similar to the blade 118, so only the differences will be discussed here. The blade 800 does not include a bevel that matches the bevel 688 of the locking flange 178. Therefore, the blade 800 engages the inner edge 692 of the flange 668 when the locking flange 178 is connected to the spindle 166 via the fastener 182. To accommodate the blade 800 without a bevel corresponding to the bevel 688 of the locking flange 178, the lower cylindrical portion 664 is extended along the rotation axis A so that the thickness T1 of the blade 800 remains the same as that of the blade 118.

[0039] Although the invention has been described in detail with reference to certain preferred embodiments, variations and modifications exist within the scope and spirit of one or more independent aspects of the invention as described.

[0040] Various features of the invention are set forth in the following claims. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] US 63 / 707,572

[0001] US 63 / 631,827

[0001] US 63 / 622,950

[0001] US 11,557,989

[0020] US 10,562,116

[0020]

Claims

[1] Motor-driven tool comprising: a housing defining a longitudinal axis; a motor housed in the housing and including a motor output shaft; a gear housing coupled to the housing; a blade guard coupled to the gear housing, in which a rotating blade is at least partially received; and a gear train at least partially received in the gear housing and configured to transmit torque from the engine output shaft to the blade, the gear train comprising: a spindle to which the blade is coupled for joint rotation, a single intermediate shaft disposed between the motor output shaft and the spindle, the intermediate shaft configured to transmit torque from the motor output shaft to the spindle, a pinion coupled for common rotation with the engine output shaft, and a ring gear coupled for common rotation with the intermediate shaft and meshing with the pinion gear, the ring gear being disposed between a first plane defined by the blade and a parallel second plane containing an axis of rotation of the motor output shaft. [2] A power tool according to claim 1, wherein the pinion is coupled to the motor output shaft by a left-hand thread arrangement. [3] A power tool according to claim 2, wherein the spindle is rotated clockwise from a reference frame along an axis of rotation of the spindle as viewed from an upper surface of the gear housing. [4] The power tool according to claim 1, wherein the motor output shaft is rotated clockwise from a reference frame along a rotational axis of the motor output shaft as viewed from a front side of the power tool. [5] A motor-driven tool according to claim 4, wherein the intermediate shaft is oriented perpendicular to the motor output shaft. [6] The power tool of claim 5, further comprising a locking pin received by the gear housing and configured for selective engagement with the ring gear to non-rotatably connect the ring gear to the gear housing. [7] The power tool of claim 5, wherein the gear train includes a drive gear coupled to the intermediate shaft for co-rotation therewith, and wherein the drive gear is disposed between the first plane and the ring gear. [8] A power tool according to claim 7, wherein the gear train comprises a driven gear coupled to the spindle for common rotation therewith, the driven gear meshing with the drive gear, and the intermediate shaft being aligned parallel to the spindle. [9] A power tool according to claim 1, wherein the gear train comprises a pair of intermediate shaft bearings configured to rotatably support the intermediate shaft, and a pair of spindle bearings configured to rotatably support the spindle, wherein at least one of the intermediate shaft bearings and at least one of the spindle bearings are arranged in the gear housing. [10] A power tool according to claim 9, wherein a second intermediate shaft bearing of the pair of intermediate shaft bearings and a second spindle bearing of the pair of spindle bearings are arranged in the blade guard. [11] The power tool according to claim 1, further comprising an axis of rotation of the spindle; a first intersection point defined by an intersection of the rotational axis of the spindle and a top surface of the gear housing; a blade cover pivotally connected to the blade guard; and a second intersection point defined by an intersection of the spindle rotation axis and a lower surface of the blade cover, wherein a distance between the first intersection point and the second intersection point is between 70 millimeters and 80 millimeters. [12] The motor-driven tool of claim 11, wherein the motor output shaft includes an end surface defining a third plane, and wherein a distance between the third plane and the rotational axis of the spindle is between 40 millimeters and 50 millimeters. [13] A power tool according to claim 11, wherein the blade has a diameter between 125 millimeters and 140 millimeters. [14] The power tool of claim 11, wherein the top of the gear housing defines a fourth plane oriented at an angle of between 20 degrees and 25 degrees relative to the first plane. [15] A power tool according to claim 11, wherein the blade guard comprises an opening extending in the direction of the longitudinal axis into which a reinforcing steel is received by a blade during a cutting operation. [16] Motor-driven rebar cutter, comprising: a housing with a longitudinal axis; a motor housed in the housing; a gear housing coupled to the housing; a blade guard coupled to the gear housing, the blade guard including an opening extending in the direction of the longitudinal axis into which a rebar is received by a blade during a cutting operation; a gear train which is at least partially housed in the gearbox housing and is configured to transfer torque from the motor to the blade; and a lighting assembly configured to project light onto the opening to illuminate a portion of the blade exposed through the opening in the blade guard. [17] A motor-driven rebar cutter according to claim 16, wherein the illumination assembly comprises a lens and a light source. [18] A motor-driven rebar cutter according to claim 17, wherein the light source is a light-emitting diode. [19] A motor-driven rebar cutter according to claim 16, wherein the lighting assembly is disposed between the gear housing and the blade guard. [20] A motor-driven rebar cutter according to claim 16, wherein the lighting assembly is arranged on the gear housing. [21] The motor-driven rebar cutter of claim 16, wherein the lighting assembly is a first lighting assembly disposed between the gear housing and the blade guard, and wherein the motor-driven rebar cutter further comprises a second lighting assembly disposed on the gear housing. [22] Motor-driven rebar cutter, comprising: a housing with a longitudinal axis; a motor housed in the housing; a gear housing connected to the housing; a blade guard coupled to the gear housing, the blade guard including an opening extending in a direction of the longitudinal axis in which rebar is received by a blade during a cutting operation; a gear train at least partially housed in the gear housing and configured to transmit torque from the motor to the blade, wherein the gear train comprises a spindle to which the blade is attached; and a blade cover pivotally connected to the blade guard between a closed position in which the blade guard and the blade cover together define a chamber in which the blade is rotatable, and an open position in which the spindle is accessible for removal of the blade. [23] The motor-driven rebar cutter of claim 22, further comprising a blade cover fastener extending through the blade guard to selectively engage the blade cover and maintain the blade cover in the closed position. [24] A motor-driven rebar cutter according to claim 23, wherein the blade cover fastener is a thumbscrew. [25] A motor-driven rebar cutter according to claim 22, further comprising a hinge, wherein the blade cover is pivotally connected to the blade guard by the hinge. [26] A motor-driven rebar cutter according to claim 22, further comprising a dust chute defined between the blade guard and the blade cover when the blade cover is in the closed position, the dust chute being tangentially oriented with respect to the blade, and dust and debris being discharged through the dust chute in response to rotation of the blade during a rebar cutting operation. [27] Motor-driven rebar cutter, comprising: a housing with a longitudinal axis; a motor housed in the housing; a gear housing connected to the housing; a blade guard coupled to the gear housing, the blade guard including an opening extending in a direction of the longitudinal axis in which rebar is received by a blade during a cutting operation; a gear train at least partially received in the gear housing and configured to transmit torque from the motor to the blade, the gear train including a spindle to which the blade is attached; and a dust chute defined at least partially by the blade guard and oriented along a central axis that is oblique relative to the longitudinal axis of the housing. [28] A motor-driven rebar cutter according to claim 27, wherein the dust chute comprises a rib disposed at one end thereof and an adjacent notch. [29] A motor-driven rebar cutter according to claim 28, further comprising a debris container coupled to the end of the dust chute and having a clamp received in the notch. [30] A motor-driven rebar cutter according to claim 27, further comprising a blade cover pivotally connected to the blade guard between a closed position in which the blade guard and the blade cover together form a chamber in which the blade is rotatable, and an open position in which the spindle is accessible for removal of the blade. [31] A motor-driven rebar cutter according to claim 30, wherein the dust chute is defined between the blade guard and the blade cover in the closed position. [32] A motor-driven rebar cutter according to claim 31, wherein the dust chute is oriented tangentially with respect to the blade and wherein dust and debris are discharged through the dust chute in response to rotation of the blade during a rebar cutting operation. [33] A motor-driven rebar cutter according to claim 27, wherein the housing comprises a battery receptacle configured to receive a battery pack, and wherein the battery receptacle comprises a tethering hook. [34] The motor-driven rebar cutter of claim 33, further comprising a tool storage container configured to receive a tool for removing the blade from the spindle. [35] Motor-driven tool, comprising: a housing with a longitudinal axis; a motor housed in the housing; a gear housing connected to the housing; a blade having an opening; a blade guard coupled to the gear housing, in which a rotating blade is at least partially received; a gear train at least partially received in the gear housing and configured to transmit torque from the motor to the blade, the gear train including a spindle with a lower recess defining a first diameter; and a locking flange and a fastener, the fastener being configured to couple the locking flange to the spindle so that the blade is clamped between the spindle and the locking flange, wherein the locking flange comprises: a first cylindrical portion received in the lower recess of the spindle, and a second cylindrical portion defining a second diameter greater than the first diameter of the lower recess, the second cylindrical portion being received within the opening of the blade. [36] The power tool of claim 35, wherein the spindle defines an axis perpendicular to the longitudinal axis, the second cylindrical portion defining an axial length measured along the spindle axis, and the axial length being less than a thickness of the blade. [37] The power tool of claim 35, wherein the locking flange includes a chamfer between the first cylindrical portion and the second cylindrical portion. [38] A power tool according to claim 35, wherein the blade includes a bevel adjacent the opening. [39] A power tool according to claim 35, wherein the blade guard comprises an opening extending in the direction of the longitudinal axis in which the reinforcing steel is received by a blade during a cutting operation. [40] The power tool of claim 35, wherein the spindle has an upper recess defining a third diameter, the third diameter being smaller than the first diameter. [41] A power tool according to claim 40, wherein the locking flange comprises a third cylindrical portion received in the upper recess of the spindle.

Images