The present invention relates to the field of handheld planers, and more particularly to bi-directional exhausting handheld planers.
Portable handheld planers are used to smooth uneven surfaces on workpieces by shaving raised portions from the workpiece until the surface is substantially smooth. The handheld planers utilize a high-speed rotary cutting tool having at least one blade that is configured to cut and remove small pieces of the workpiece (chips) until the smooth surface is achieved. The blades are located within the housing of the planer, and extend therefrom to contact the surface of the workpiece to be planed. The extent to which the blades extend beyond the housing can be adjusted to provide a deeper cut into the workpiece such that more of the workpiece is removed with each rotation of the cutting tool. As the small pieces of the workpiece are removed, they are generally expelled from the handheld planer through an exhaust port located on one side of the housing of the planer.
The cutting tool is rotated by a motor. The motor can be powered by an electric cord or by a removable battery pack. The motor includes a fan that produces a stream of air that is directed through the central portion of the housing. As the stream of air passes through the housing, the chips and the air stream are combined such that the air carries the chips out through an exhaust port.
The handheld planers provide an advantage over the stationary planers by allowing the user more freedom to move about the workpiece, work at a variety of angles, and greater accessibility to a workpiece. Handheld planers also provide for bi-directional exhaustion of the chips removed from the workpiece such that the user is provided with the option to choose from which exhaust port the chips are to be expelled. The advantage of the bi-directional exhausting of the chips allows the user to hold the planer in either hand when working so as to further increase the portability of the planer. However, bi-directional planers, in which the air stream from the motor flowing transverse to the longitudinal axis of the planer through the housing, often have problems with the chips clogging the exhaust port that is opposite the direction of the normal flow of air. There exists a need for an improved bidirectional exhausting planer that eliminates or substantially reduces the likelihood of clogging of the exhaust port while the user is working.
One aspect of the present invention provides an embodiment of a handheld planer that allows for bi-directional exhaustion of chips removed from a workpiece so that the user is allowed ambidextrous operation of the planer. One embodiment of such a planer includes a housing that can have a pair of exhaust ports from which the removed chips are expelled. The planer also includes a motor that is operatively connected to a rotatable fan and cutting tool. The cutting tool is located within the cutting chamber within the housing and as the cutting tool rotates chips are removed from the workpiece. An insert can also be located within the cutting chamber so that as the chips are removed by the cutting tool, the insert pre-directs the chips toward one of the exhaust ports. The planer can also include an adjustable flap that can be selectively positioned by the user so the user can choose from which exhaust port the chips are to be expelled.
In another embodiment, the insert located within the cutting chamber has a ribbed, vaned, or undulating surface having a plurality of raised, angled ribs or protrusions in which each raised rib is connected to an adjacent rib by a sloped surface.
Another aspect of the present invention provides a method for planing a workpiece using a bi-directional exhausting handheld planer. The method includes providing a housing that has a pair of exhaust ports and a cutting chamber that is located within the housing. The method also includes rotatably mounting a cutting tool within the cutting chamber and attaching a pre-directing insert within the cutting chamber so that the chips are pre-directed toward one of the exhaust ports. Finally, the method includes selecting the port from which the chips are to be exhausted by positioning a flap in either a first or second position.
Advantages of the present invention will become more apparent to those skilled in the art from the following description of the preferred embodiments of the invention which have been shown and described by way of illustration. As will be realized, the invention is capable of other and different embodiments, and its details are capable of modification in various respects. Accordingly, the drawings and description are to be regarded as illustrative in nature and not as restrictive.
Both handles 20, 22 allow the user to control the movement and direction of the planer 10. By grasping the rear handle 20 and the forward handle 22, the user can maneuver the planer 10 into areas that cannot be readily accessed using stationary tabletop planers. The electrical cord 28 provides electrical power to a motor 27 which, in turn, drives a cutting tool 30 (
An adjustment knob 32 is located near the front end of the second portion 16 of the housing 12 for adjusting the height of the cutting tool 30 with respect to the workpiece 60 (
The first portion 14 of the housing 12 includes a first exhaust port 36 protruding laterally from the housing 12 in a transverse direction with respect to the length of the planer 10 (i.e., transverse to the longitudinal direction of the planer). The second portion 16 of the housing 12 includes a second exhaust port 38 (shown in hidden lines) extending laterally from the housing 12 in the opposite direction of the first exhaust port 36, as illustrated in
A switch 40 is disposed centrally between the opposing exhaust ports 36, 38. The switch 40 operates a flap 42 (
Because the chips 21 can be expelled through either of the two exhaust ports 36, 38 and because the pair of handles 20, 22 are centrally located, the user can operate the planer 10 from either side. In addition, because the chips 21 can be selectively exhausted from either port 36, 38, the chips 21 can be expelled on the side of the planer 10 opposite the operator. In other words, the planer provides ambidextrous operation.
A fan cover 52, as illustrated in
The motor 27 of the planer of the illustrated embodiment is disposed within the housing and is operatively connected to the fan located externally of the housing in which the preferred direction of air flow from the fan passes in a transverse manner through the housing toward the exhaust port on the side of the housing opposite the side to which the fan extends. In an alternative embodiment, the fan can be mounted in a likewise manner on the opposing side of the housing such that the normal flow of air through the housing is in the direction opposite that of the illustrated embodiment. In a further alternative embodiment, the fan can be disposed within the housing such that the normal flow of air is generally parallel to the longitudinal direction of the planer. It should be understood by one skilled in the art that the flow of air through the housing can be any direction sufficient to guide and carry the removed chips through an exhaust port.
As shown in
The cutting tool 30 includes a block 62 having a central bore 63 through the longitudinal center of the block 62 in order to allow a rotatable pin to be passed therethrough. The pin is rotatably mounted to the housing at each distal end by a bearing element (not shown). A motor 27 is operatively connected to the trigger 26 such that the actuation of the trigger activates the motor 27 that, in turn, drives the rotation of the fan 46 and the cutting tool 30 so that a pair of blades 64 are rotated simultaneously with the block 62. The blades 64 are attached to opposing surfaces of the block 62 in a manner such that each blade 64 extends beyond the edge of the surface of the block 62 to which it is mounted. The blades 64 extend beyond their respective edge of the block 62 in opposing directions relative to the block 62 so that each blade 64 contacts the workpiece 60 one time for each complete rotation of the block 62. Each time a blade 64 contacts the surface of the workpiece 60 a chip 21 is removed from the workpiece 60 until the surface of the workpiece 60 is planar.
As the loose chips 21 are removed from the workpiece 60, the rotation of the cutting tool 30 forces the chips 21 into the cutting chamber 58 away from the workpiece 60 and toward the passageway 44, as illustrated in
The flap 42, illustrated in
When the flap 42 is in the first position of one embodiment of a planer without a pre-directing insert, the air flow and loose chips 21 must reverse direction in order to be expelled from the first exhaust port 36, turbulence is created as a result of the constant collision between the loose chips 21 as the direction of the air flow is reversed. Turbulence caused by the constant collision of the chips and re-directing the air flow such that it exits the housing 12 in the opposite direction from which it entered may reduce the efficiency by which the chips 21 are expelled from the planer 10. This turbulence is remedied by a pre-directing insert 66 disposed within the cutting chamber 58. The turbulence is generally not present when the flap 42 is in the second position because the direction of the air flow is only slightly altered as it enters the housing 12 and the passageway 44 such that the air flows freely in the transverse direction through the housing 12 and combines with the chips 21, and the flow of air and chips are thus easily expelled from the second exhaust port 38.
The pre-directing insert 66, as illustrated in
The insert 66 has a generally triangular cross-section having a pair of surfaces 68, 70 and a ribbed surface 72, as shown in
The insert 66 is secured within the cutting chamber 58 by a pair of screws 78 that are inserted through the housing 12 and into the side surfaces 78 of the insert 66. The insert 66 is disposed within the cutting chamber 58 such that the length of the insert is oriented in a transverse manner relative to the longitudinal direction of the planer 10 and parallel to the length of the cutting chamber 58, as illustrated in
In operation, as the loose chips 21 are removed from the workpiece 60 and are directed toward the passageway 44, the loose chips 21 contact the insert 66 in a manner in which the angled ribs 74 pre-direct the chips 21 toward the first exhaust port 36. Thus, when the user selects the flap 42 to be in the first position such that the chips 21 are expelled from the first exhaust port 36, the loose chips 21 are already pre-directed toward the first exhaust port 36, and the turbulence that was caused by the impedance of the chips 21 with each other as they were re-directed is reduced or eliminated. Such a reduction or elimination of turbulence among the loose chips 21 during the re-direction of the chips with the aid of the re-directed air flow reduces or eliminates clogging of the first exhaust port 36, as shown in
When the user selects the flap 42 to be in the second position such that the chips 21 are expelled from the second exhaust port 38, the air flow through the housing 12 and passageway 44 is much more powerful than when the flap is in the first position because the air is not re-directed in the opposite direction. Hence, the additional pressure of the air flow through the housing 12 and passageway 44 easily combines with the pre-directed chips 21 to force a slight alteration in the direction of the chips in order for the chips to be expelled from the second exhaust port 38, as shown in
While preferred embodiments of the invention have been described, it should be understood by one skilled in the art that the invention is not so limited and modifications may be made without departing from the invention. The scope of the invention is defined by the appended claims, and all devices that come within the meaning of the claims, either literally or by equivalence, are intended to be embraced therein.