Patent Description:
Conventional material removal machines, such as saws, grinders, and/or polishers, for example, use belt tensioner devices positioned along a length of a belt. The belt tensioner devices are conventionally configured to impinge upon a belt to adjust tension in the belt. However, these belt tensioner devices are imprecise and provide a limited range of potential belt tensions. Additionally, the belt tensioner devices may constitute obstructions when attaching and/or removing the belt due to the placement of the belt tensioner devices near the belt.

Limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with the present disclosure as set forth in the remainder of the present application with reference to the drawings.

From <CIT> there is known a material removal apparatus, comprising a spindle configured to retain a material removal tool, a spindle pulley secured to the spindle, the spindle pulley configured to actuate the spindle and a hub having a body retaining the spindle such that an outer diameter of the body is less than the inner diameter of the spindle housing, the hub configured to change a position of the spindle pulley, the apparatus further comprising a hub lock configured to prohibit movement of the hub when engaged, and allow movement of the hub when disengaged.

From <CIT> there is also known a method of adjusting belt tension in a material removal machine, comprising adjusting a position of a spindle pulley of the material removal machine via a hub of the material removal machine, wherein the spindle pulley is configured to actuate a material removal tool of the material removal machine, wherein the material removal machine further comprises a hub having a body retaining a spindle such that an outer diameter of the body is less than the inner diameter of the spindle housing, the hub configured to change a position of the spindle pulley and a hub lock configured to prohibit movement of the hub when engaged, and allow movement of the hub when disengaged.

The present disclosure is directed to belt tensioning apparatus for material removal machines as set forth in the claims.

These and other advantages, aspects and novel features of the present disclosure, as well as details of an illustrated example thereof, will be more fully understood from the following description and drawings.

Where appropriate, the same or similar reference numerals are used in the figures to refer to similar or identical elements. For example, reference numerals utilizing lettering (e.g., upper support rail 202a, lower support rail 202b) refer to instances of the same reference numeral that does not have the lettering (e.g., support rails <NUM>).

Preferred examples of the present disclosure may be described hereinbelow with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail because they may obscure the disclosure in unnecessary detail. For this disclosure, the following terms and definitions shall apply.

As used herein, the terms "about" and/or "approximately," when used to modify or describe a value (or range of values), position, orientation, and/or action, mean reasonably close to that value, range of values, position, orientation, and/or action. Thus, the examples described herein are not limited to only the recited values, ranges of values, positions, orientations, and/or actions but rather should include reasonably workable deviations.

As used herein, "and/or" means any one or more of the items in the list joined by "and/or".

Some examples of the present disclosure relate to a material removal apparatus, comprising a spindle configured to retain a material removal tool, a spindle pulley secured to the spindle, the spindle pulley configured to actuate the spindle, and a hub retaining the spindle, the hub configured to change a position of the spindle pulley.

In some examples, the apparatus further comprises an actuator pulley configured actuate the spindle pulley via a belt, the hub configured to change the position of the spindle pulley relative to the actuator pulley. In some examples, the hub is configured to move the spindle pulley from a first position at a first distance from an actuator pulley, to a second position at a second distance from the actuator pulley, the first distance being different from the second distance. In some examples, the belt has a first tension when the spindle pulley is at the first position, and a second tension when the spindle pulley is at the second position, the first tension being different from the second tension. In some examples, the apparatus further comprises an actuator configured to actuate the actuator pulley. In some examples, the hub is configured to change the position of the spindle pulley by changing the position of the spindle. In some examples, the hub is configured to engage a hub moving tool. In some examples, the apparatus further comprises a hub lock configured to prohibit movement of the hub when engaged, and allow movement of the hub when disengaged. In some examples, the hub lock is secured to a spindle housing that encircles at least a portion of the hub and the spindle. In some examples, the hub lock is configured to compress the spindle housing when engaged.

Some examples of the present disclosure relate to a method of adjusting belt tension in a material removal machine, comprising adjusting a position of a spindle pulley of the material removal machine via a hub of the material removal machine, wherein the spindle pulley is configured to actuate a material removal tool of the material removal machine.

In some examples, adjusting the position of the spindle pulley comprises adjusting the position of the spindle pulley with respect to an actuator pulley of the material removal machine. In some examples, adjusting the position of the spindle pulley comprises moving the spindle pulley from a first position at a first distance from an actuator pulley, to a second position at a second distance from the actuator pulley, the first distance being different from the second distance. In some examples, a belt connecting the spindle pulley to the actuator pulley has a first tension when the spindle pulley is at the first position, and a second tension when the spindle pulley is at the second position, the first tension being different from the second tension. In some examples, the method further comprises actuating the material removal tool via the spindle pulley. In some examples, actuating the material removal tool via the spindle pulley comprises translating actuation of the actuator pulley into actuation of the spindle pulley through the belt connecting the actuator pulley and the spindle pulley. In some examples, the method further comprises gaining access to a hub lock of the material removal machine and unlocking the hub via the hub lock before adjusting the position of the spindle pulley. In some examples, the method further comprises gaining access to a hub lock of the material removal machine and locking the hub via the hub lock after adjusting the position of the spindle pulley. In some examples, the spindle pulley is secured to a spindle of the material removal machine, the material removal tool is retained on the spindle, and the spindle is retained by the hub. In some examples, adjusting the position of a spindle pulley via the hub comprises adjusting the hub using a tool that engages with engagement features of the hub.

Some examples of the present disclosure relate to an improved belt tensioning apparatus for a material removal machine. In some examples, the material removal machine includes a material removal tool (e.g., a saw blade, an abrasive saw, a polisher, a grinder, and/or more general material preparation and/or testing tool). The material removal tool is mounted on a spindle that is actuated (e.g., turned, spun, etc.) by a spindle pulley, which is in turn actuated by an actuator pulley. A flexible belt stretches between (and/or connects) the spindle pulley and the actuator pulley. The belt has a belt tension that changes depending on the distance (e.g., how far) the belt is stretched between the spindle pulley and actuator pulley, with increased distance correlated with increased tension.

Some examples of the present disclosure use a movable hub instead of a conventional belt tensioner device to change tension in the belt. In some examples, the spindle is retained by the movable hub, such that movement of the hub translated into movement of the spindle. Because the spindle pulley is securely attached to the spindle, movement of the hub translates into movement of the spindle pulley. This movement of the spindle pulley changes a distance between the spindle pulley and the actuator pulley, thereby changing the tension in the belt connecting the spindle pulley and the actuator pulley. Thus, belt tension may be increased by moving the hub to a position where the spindle pulley is farther from the actuator pulley, and decreased by moving the hub to a position where the spindle pulley is closer to the actuator pulley. The hub may be locked in place once a desired position is reached.

In some examples, the movable hub makes it easier to attach and/or remove the belt from the pulleys. While efficient machine operation may require an increased tension in the belt, it may be easier to attach and/or remove the belt when there is a decreased tension in the belt. The movable hub allows for relatively easy adjustment of belt tension, which allows for easy transition between a belt tension ideal for attachment/removal and a belt tension ideal for machine operation. Additionally, the movable hub is not positioned along the length of the belt like a conventional belt tensioner, thereby removing an obstruction to attachment and/or removal of the belt. Further, the hub allows for more precise tensioning and/or a wider range of available belt tensions than a conventional belt tensioner device.

<FIG> shows a simplified illustration of an example material removal system <NUM>. As shown, the material removal system <NUM> includes a material removal assembly <NUM> and a table <NUM> substantially enclosed within a cabinet <NUM> (and/or housing). The table <NUM> is configured to retain a material sample (not shown), upon which the material removal assembly <NUM> may operate. In the example of <FIG>, the material removal assembly <NUM> further includes a user interface (UI) <NUM> and a power source <NUM>.

<FIG> shows a rear perspective view of an example material removal assembly <NUM>. In the example of <FIG>, the material removal assembly <NUM> includes a material removal machine <NUM>. As shown, the material removal machine <NUM> is retained on an upper support rail 202a and a lower support rail 202b between a first end plate 204a and a second end plate 204b. The support rails <NUM> extend through the material removal machine <NUM> and are retained by the end plates <NUM>. More particularly, the support rails <NUM> extend through sleeves <NUM> of the material removal machine <NUM> (see, e.g., <FIG>). An actuation shaft <NUM> also extends between the end plates <NUM> and through an actuation nut <NUM> of the material removal machine <NUM> (see, e.g., <FIG>). In some examples, rotation of the actuation shaft <NUM> in conjunction with engagement with the actuation nut <NUM> causes movement of the material removal machine <NUM>. In some examples, an actuation unit <NUM> may further rotate the lower support rail 202b, and thereby cause rotational movement of the end plates <NUM> and material removal machine <NUM>.

<FIG> show various views of the material removal machine <NUM>. <FIG> is an enlarged rear perspective view, while <FIG> and <FIG> are side views of the material removal machine <NUM>, with some of the other elements of the material removal assembly <NUM> removed for the sake of clarity. As shown, the material removal machine <NUM> includes a material removal tool <NUM> (e.g., a saw blade, abrasive saw, grinder, polisher, etc.) retained on a spindle <NUM> that is at least partially encased in a spindle housing <NUM> of the support <NUM>. In the example of <FIG>, the material removal tool <NUM> is a disc.

In the example of <FIG>, the support <NUM> comprises two substantially parallel support plates <NUM>: a first support plate 307a and a second support plate 307b. The support plate 307a includes the nut <NUM>. A shield <NUM> connected to the support plate 307a partially encloses (and/or encases) the material removal tool <NUM>. The support plates <NUM> are connected through the sleeves <NUM> (upper sleeve 308a and lower sleeve 308b), the spindle housing <NUM>, and a tool actuator housing <NUM>. The tool actuator housing <NUM> encloses a tool actuator <NUM> and/or tool actuator controller <NUM>. In some examples, the tool actuator <NUM> and/or tool actuator controller <NUM> may be powered by the power source <NUM>, or may be powered by a separate power source retained within the tool actuator housing <NUM>.

In the example of <FIG> and <FIG>, the tool actuator <NUM> is in mechanical communication with an actuator pulley <NUM>. The tool actuator <NUM> (e.g., an electrical motor) is configured to actuate (e.g., move, turn, spin, rotate, etc.) the actuator pulley <NUM>, such as in response to one or more signals from the actuator controller <NUM>. As shown, the actuator pulley <NUM> is mechanically connected to a spindle pulley <NUM> via a belt <NUM>. As shown, the actuator pulley <NUM>, spindle pulley <NUM>, and belt <NUM> are substantially encased within an arm <NUM> of the support <NUM>. The belt <NUM> translates actuation (e.g., movement, rotation, turning, spinning, etc.) of the actuator pulley <NUM> into actuation (e.g., movement, rotation, turning, spinning, etc.) of the spindle pulley <NUM>. The spindle pulley <NUM> is secured to the spindle <NUM>, such that actuation (e.g., movement, rotation, turning, spinning, etc.) of the actuator pulley <NUM> by the tool actuator <NUM> translates into actuation (e.g., movement, rotation, turning, spinning, etc.) of the spindle <NUM> and/or material removal tool <NUM> via the spindle pulley <NUM>.

In the example of <FIG>, the spindle <NUM> extends through an approximate center (and/or central aperture) of the material removal tool <NUM> and the spindle pulley <NUM>. A fastener <NUM> attaches to an end of the spindle <NUM> and secures the material removal tool <NUM> on the spindle <NUM> between flanges <NUM>. As shown, the fastener <NUM> is a nut, but in other examples the fastener <NUM> may be a nut, bolt, screw, nail, and/or any other type of appropriate fastener.

In the example of <FIG>, the spindle <NUM> is retained by the hub <NUM>. In the examples of <FIG> and 3e, the hub <NUM> is substantially cylindrical, and includes a collar <NUM> at an end of the hub <NUM>, with a body <NUM> extending from the collar <NUM>. As shown, the collar <NUM> has a larger outer diameter than the body <NUM>. The collar <NUM> also includes pin holes <NUM> around the circumference of the collar <NUM>. The pin holes <NUM> are configured to engage pins of a pin wrench, allowing the pin wrench to grip and/or move (e.g., turn, rotate, spin, etc.) the collar <NUM> when the collar is unlocked.

In the example of <FIG>, plate seals <NUM> and ball bearings <NUM> are pinched between the hub <NUM> and the spindle <NUM> to help keep the spindle <NUM> in place, while still allowing the spindle <NUM> to move (e.g., spin, rotate, turn, etc.) within the hub <NUM>. The plate seals <NUM> additionally serve as seals, to keep lubricant within the hub <NUM>, and debris out of the hub <NUM>. As shown, an additional seal <NUM> attaches to the collar <NUM> of the hub <NUM> and/or plate seal 344a. In the example of <FIG>, the body <NUM> of the hub <NUM> is retained within the spindle housing <NUM>, such that an outer diameter of the body <NUM> is less than the inner dimeter of the spindle housing <NUM>. As shown, the collar <NUM> is not retained within the spindle housing <NUM>, but is rather substantially aligned (and/or collinear) with the spindle housing <NUM>, such that the collar <NUM> has an outer diameter approximately equal to the spindle housing <NUM>.

In the examples of <FIG> and 3e, the hub <NUM> includes a cylindrical bore <NUM> that extends through the hub <NUM> off center (e.g., shifted from a central axis of the hub <NUM>), such that the hub <NUM> has an eccentric arrangement. The spindle <NUM> is secured within an approximate center of the bore <NUM>. This organization results in the spindle <NUM> and spindle pulley <NUM> being retained by the hub <NUM> at a shifted, off-center, and/or eccentric position with respect to the hub <NUM>, such as shown in the examples of <FIG>. Thus, when the hub <NUM> is rotated (and/or turned, spun, moved, etc.), the spindle <NUM> and/or spindle pulley <NUM> are moved to different positions, rather than simply being spun (and/or rotated, turned, etc.) in place. In the example of <FIG>, the spindle pulley <NUM> is advantageously positioned within the arm <NUM> with enough space so that this movement is possible. As the actuator pulley <NUM> is substantially fixed with respect to other components of the material removal machine <NUM> (e.g., the spindle pulley <NUM>, hub <NUM>, etc.), movement of the spindle pulley <NUM> results in a change in distance between the spindle pulley <NUM> and the actuator pulley <NUM>. This change in distance in turn results in a change in tension of the belt <NUM> connecting the spindle pulley <NUM> and the actuator pulley <NUM>.

<FIG>, shows an exaggerated example of movement of the hub <NUM> when the hub <NUM> is unlocked and, through the hub <NUM>, movement of the spindle pulley <NUM>, spindle <NUM>, and/or material removal machine <NUM>. The difference in dimensions of the hub <NUM> and spindle pulley <NUM> are exaggerated in <FIG>, to make the operation clearer. In <FIG>, the spindle pulley <NUM> is at a first position a first distance D1 from the actuator pulley <NUM>. This results in a first tension in the belt <NUM>. In the example of <FIG>, the spindle pulley <NUM> has been moved to a second position a second distance D2 from the actuator pulley <NUM>. This results in a second tension in the belt <NUM>. As the first distance D1 is less than the second distance D2, the first tension will be less than the second tension. Thus, the first position of <FIG> may be better for attaching and/or removing the belt, while the second position of <FIG> may be better for operation of the material removal machine <NUM> (and/or material removal tool <NUM>). <FIG> shows the spindle pulley <NUM> at a third position a third distance D1 from the actuator pulley <NUM>. This results in a third tension in the belt <NUM>. As the first distance D1 is less than the third distance D3, the first tension will be less than the third tension. The second distance D2 is also less than the third distance D3, so the second tension will be less than the third tension. Thus, the first or second positions of <FIG> and <FIG> may be better for attaching and/or removing the belt, while the third position of <FIG> may be better for operation of the material removal machine <NUM> (and/or material removal tool <NUM>).

In the example of <FIG>, a hub plate <NUM> attaches to the spindle housing <NUM> proximate to the material removal tool <NUM>, such that the flange 342b abuts the hub plate <NUM>. The hub plate <NUM> is configured to compress the spindle housing <NUM> when the hub plate <NUM> is tightened onto the spindle housing <NUM>, so as to lock the hub <NUM> in place. More particularly, when the hub plate <NUM> compresses the spindle housing <NUM>, the spindle housing <NUM> squeezes tightly against the hub <NUM>, preventing movement (e.g., rotation, turning, spinning, etc.) of the hub <NUM>. When the hub plate <NUM> is loosened, the spindle housing <NUM> is allowed to expand somewhat, giving the hub plate <NUM> room to move (e.g., spin, turn, rotate, etc.) within the spindle housing <NUM>. In some examples, hub plate fasteners (not shown) may be used to loosen and/or tighten the hub plate <NUM>. Thus, the hub plate <NUM> provides a mechanism through which the hub <NUM> may be locked and/or unlocked.

In operation, an operator may initially attach the belt <NUM> to the material removal machine <NUM>. In order to minimize the human effort necessary to stretch the belt, the operator may wish to move the hub <NUM> so that the spindle pulley <NUM> is closer to the actuator pulley <NUM>. Thus, the operator may unlock the hub <NUM> by loosening the hub plate <NUM>. In order to get to the hub plate <NUM> for loosening, the fastener <NUM>, material removal tool <NUM>, and/or flanges <NUM> may need to be removed from the spindle <NUM>. While the removal of these components to access the hub plate <NUM> may be slightly inconvenient, the obstructed access may help prevent accidental loosening of the hub plate <NUM>. Once the hub plate <NUM> is loosened, the operator may adjust the hub <NUM>, such as via a pin wrench for example. For example, the operator may adjust the hub <NUM> to position similar to the first position illustrated in <FIG>. The operator may then attach the belt <NUM> to the spindle pulley <NUM> and/or actuator pulley <NUM>, stretching the belt <NUM> as necessary. Once the belt <NUM> is attached, the operator may move the hub <NUM> to a position where the belt <NUM> will have a higher tension, which may be better for operation of the material removal machine <NUM> (and/or material removal tool <NUM>). For example, the operator may adjust the hub <NUM> to position similar to the second or third position illustrated in <FIG> and <FIG>. Once the hub <NUM> has been appropriately positioned, with the belt attached, the operator may tighten the hub plate <NUM> so as to lock the hub <NUM> in place, then reattach the flanges <NUM>, material removal tool <NUM>, and/or fastener <NUM>. Finally, the material removal machine <NUM> may be ready for operation through actuation of the material removal tool <NUM> via the tool actuator <NUM>, actuator pulley <NUM>, belt <NUM>, spindle pulley <NUM>, and/or spindle <NUM>.

Claim 1:
A material removal apparatus, comprising:
a spindle (<NUM>) configured to retain a material removal tool (<NUM>);
a spindle pulley (<NUM>) secured to the spindle, the spindle pulley (<NUM>) configured to actuate the spindle; and
a hub (<NUM>) having a body (<NUM>) retaining the spindle (<NUM>) such that an outer diameter of the body (<NUM>) is less than the inner diameter of a spindle housing (<NUM>), the hub (<NUM>) configured to change a position of the spindle pulley (<NUM>),
the apparatus further comprising a hub lock configured to prohibit movement of the hub (<NUM>) when engaged, and allow movement of the hub when disengaged,
wherein the hub lock is secured to the spindle housing (<NUM>) that encircles at least a portion of the hub (<NUM>) and the spindle (<NUM>),
wherein the material removal apparatus further comprises a hub plate (<NUM>) that is attached to the spindle housing (<NUM>) proximate to the material removal tool (<NUM>); and
wherein the hub lock is configured to compress the spindle housing (<NUM>) when the hub plate (<NUM>) is tightened onto the spindle housing (<NUM>), so as to lock the hub (<NUM>) in place.