Patent Application
20060264161
The present invention relates to the field of woodworking and particularly to a belt sander.
Woodworkers often have to smooth the surface of a workpiece prior to the completion of a woodworking project. For example, most workpieces require at least a minimal amount of sanding in order to remove any excess glue or rough edges prior to completion of the project. Currently, a number of different types of sanders are available to improve the surface quality and appearance of a workpiece. Such sanders range from a piece of sandpaper wrapped around a scrap of wood to motorized sanders including orbital sanders and quarter pad finishing sanders.
The selection of a specific type of sander depends upon the condition and type of workpiece. For example, for finer finishing work a quarter pad finishing sander or an orbital sander may be utilized. Both a quarter pad finishing sander and orbital sander utilize a sandpaper pad connected onto a plate on the bottom of the sander. Further, the height and shape of the housing of a quarter pad finishing sander is substantially similar to that of an orbital sander (e.g. relatively tall and conical in shape). The pattern of movement is different, however, between such sanders whereby the quarter pad finishing sander moves the pad back and forth while an orbital sander moves such pad in a small circular motion. Due to the type of action implemented by these sanders, however, if a woodworker desires to remove material quickly a more aggressive sander might be employed.
Although the conventional motorized sanders, e.g. orbital sanders and quarter pad finishing sanders, have increased the ease in which sanding may be performed, such sanders are disadvantageous in certain circumstances. First, current orbital sanders and quarter pad sanders are often relatively tall which results in a greater distance between the operator's hand and the work piece and the chance that the sander may drift. Further, the shape of such sanders is often conical which is difficult to grasp and thus, difficult for the user to control. For example, a user is often required to grip the sander in such a manner that one's hand is perpendicular to the sanding assembly. In addition, such sanders are designed mostly for finer finishing work in which the sander is designed to remove material more slowly when compared to other configurations of sanders. The currently available more aggressive type of sanders are often undesirable for they are typically large, bulky, and cumbersome to operate.
Therefore, it would be desirable to design a sander with a contour and size which allowed the user to exert better control over such sander while in use.
Accordingly, the present invention is directed to a belt sander. In exemplary embodiments, the belt sander includes a high voltage direct current motor for providing rotational torque to the sander is disclosed. In an exemplary embodiment, a motor housing generally encompasses the motor for enclosure of the motor and motor control components. The motor housing is generally contoured to be received by a human hand and sized to a generally sized human hand. Further, a sanding assembly is operationally coupled to the motor housing for providing an abrasive surface to be used to sand a desired surface. The sanding assembly includes a plurality of rollers, the plurality of rollers including a front roller and a rear roller, the front roller being of a smaller diameter than the rear roller. The motor housing generally contoured to be received by the human hand and sized to the generally sized human hand allows a user to control the belt sander with one hand.
In specific aspects of the present invention, the motor is oriented in line with the direction of travel of the sanding assembly. Further, a power switch may be disposed within the front of the housing to control the transmission of electricity to the motor. In addition, a variable speed switch or dial may be disposed within the front of the housing to allow a user to vary the speed of the motor. In additional embodiments, the motor housing is contoured so that a user's hand and wrist occupy different planes during use of the belt sander. Moreover, the belt sander may include a gearing system for transmitting torque to the sanding assembly. In an exemplary embodiment, such gearing system is enclosed by a gear housing to prevent dust and debris from entering the gearing system and for dampening noise. In still further embodiments, the motor housing contouring defines an indentation for a user's thumb.
It is to be understood that both the forgoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate an embodiment of the invention and together with the general description, serve to explain the principles of the invention.
The numerous advantages of the present invention may be better understood by those skilled in the art by reference to the accompanying figures in which:
Reference will now be made in detail to the presently preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. It is to be appreciated that corresponding reference numbers refer to generally corresponding structures.
Referring in general to
Referring specifically to
As illustrated by
In exemplary embodiments, the housing is formed of materials which include the desired rigidity, machinability and impact resistance such as polyvinyl chloride (PVC), acrylonitrate-butadiene-styrene (ABS), ultra high molecular weight polyethylene (UHMW) plastic, and the like. In additional embodiments, soft grip sides 108 and top 109 are included to reduce vibration transferred to the user and allow a user to maintain efficient control over the sander 100 by providing an easier to grip surface. In such embodiments, the soft grip sides 108 may be formed of elastomeric material such as foam, rubber, rubber impregnated with gel, or the like. It is contemplated that gripping pads may be included in addition to or instead of soft grips sides.
In further additional embodiments of the present invention, the belt sander 100 includes a power cord 134 and switch 110 to control power transmission to the motor 102 and motor components. In an exemplary embodiment, the power cord 134 is located on the rear of the motor housing 106 to allow operation of the belt sander 100 without interference of the power cord 134. The rear of the motor housing 106 being defined as the part of the sander 100 which is covered by the a user's wrist and the lower edge of a user's palm. In further exemplary embodiments, the power switch 110 is located on the front of the housing 106 relative to the power cord 134. Such configuration allows a user to grip the belt sander 100 via the side grips 108, gripping pads or the like while minimizing inadvertent manipulation of the power switch 110 (as illustrated in
In additional embodiments, the belt sander 100 includes a mechanism to allow for speed variation. For example, in one embodiment, the power switch 110 is a multi-positional switch allowing a user to vary motor speed as desired. Use of the HVDC motor, as described above, allows the belt sander to be capable of operating at various speeds. In an exemplary embodiment, the switch 110 is located on the front of the motor housing 106 relative to the power cord 134 allowing a user to alter the speed of the sander without the user having to vary gripping position orientation. In further exemplary embodiments, the belt sander 100 includes a separate switch/dial for speed variation. In such embodiment, the additional switch/dial may also be located on the front of the motor housing 106 relative to the power cord 134. The present configuration allows motor speed to be varied without the user having to vary gripping position orientation. For example, the switch/dial may be configured so that it may be manipulated by a user's index finger. Further, the dial may denote pre-defined increments of variations in speed. In addition, the dial may also allow for smaller incremental variations in speed within the pre-defined increments.
In an exemplary embodiment, the belt sander includes the sanding assembly 104. Such assembly 104 is enclosed by a skirt 112 of the motor housing 106. In exemplary embodiments, the skirt 112 is formed of materials which include the desired rigidity, machinability and impact resistance such as polyvinyl chloride (PVC), acrylonitrate-butadiene-styrene (ABS), ultra high molecular weight polyethylene (UHMW) plastic, and the like. In an advantageous embodiment, the skirt 112 is light weight and contoured to the general size of the motor housing 106. Further, the skirt 112 protects the components within the sanding assembly 104 from damage as well as prevents dust and debris from entering the assembly 104.
As illustrated in
In additional exemplary embodiments, the sanding assembly 104 includes a pulley system which transmits the torque provided from the motor 102 to the sanding assembly 104. The pulley system includes a plurality of pulleys and belts. As illustrated in
In even further exemplary embodiments, as illustrated in
Additionally, as demonstrated in
In additional exemplary embodiments, the sanding assembly 104 includes a belt tensioning adjuster 130 allowing a user to apply or release tension to the sanding belt 128. For example, the sanding assembly 104 may include an extending platen to extend or shorten the path of travel of the sanding belt or to extend an idle roller forward and back. Further, an additional belt tracking adjuster 132 may also be included to allow for tool free alignment of the sanding belt 132. In an exemplary embodiment, the belt tracking adjuster 132 is included within the front of the sanding assembly 104. For example, if the sanding belt 128 starts to track to one side of the sander 100, a user may adjust the belt tracking by rotating the belt tracking adjuster 132 whereby clockwise movement of the belt tracking adjuster moves the belt to the right when facing the sander 100 while counterclockwise movement moves the belt to the left.
In use, the motor provides torque to the sanding assembly 104 via a gearing system 126 (e.g. a cross helical or worm drive gearing system) wherein such system transmits power to the drive belt pulley 118. In turn, the pitch belt 122 then transfers rotation from the drive belt pulley 118 to the driven pulley 120 and the rear sanding belt roller 116. The instant configuration thereby allows a user to operate the belt sander 100 vertically, horizontally or at various angles in-between.
In additional embodiments, it is contemplated that the belt sander 100 may include mechanisms designed to minimize or eliminate dust generated by fast sanding action. For example, in one embodiment, the belt sander 100 may include an integrated dust collection system which allows dust to be collected within a receptacle during operation. In an additional embodiment, the belt sander 100 may include a dust outlet allowing the belt sander 100 to be directly connected to a conventional shop vacuum hose or a centralized vacuum system. In further exemplary embodiments, a dust collection skirt may be included for managing dust generated during use. In an exemplary embodiment, the dust collection skirt may be located towards the rear of the sander 100 towards the power cord 134 in order to not interfere with the operation of the sander 100 and to direct dust away from the workpiece.
It is believed that the present invention and many of its attendant advantages will be understood by the forgoing description. It is also believed that it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely an explanatory embodiment thereof. It is the intention of the following claims to encompass and include such changes.
