Patent Application
20190134700
Example embodiments generally relate to power tools and, in particular, relate to a riveter with a safety interlock and/or pneumatic valve assembly.
Power tools are commonly used across all aspects of industry and in the homes of consumers. Power tools are employed for multiple applications including, for example, drilling, tightening, sanding, component joining, and/or the like. For some component joining applications, riveters (e.g., rivet guns or other rivet setting tools) may be preferred. Riveters that are used in some applications may require operators to set a plurality of rivets in succession to joins surfaces or adjacent panels of, for example, an aircraft fuselage.
In such an environment, safety is paramount. Thus, safety interlocks may be provided to ensure that, for example, the operator does not accidentally actuate the riveter other than when specifically desired. However, if the safety interlock is required to be operated before each and every actuation of the riveter, the burden on the operator may be large and compliance may become a concern in cases where many rivets are typically set in series. In fact, in some cases, operators may permanently disable the safety interlock to avoid the burden.
To address this issue, a safety interlock that can ensure positive control of the tool and intent of the operator to set are confirmed before the riveter can actuate, but thereafter a series of actuations can be provided without overburdening the operator between such actuations.
Some example embodiments may enable the provision of a riveter that has a safety interlock that is secure (e.g., cannot be tampered with) and effective. Some example embodiments may also or alternatively provide for improved progressivity of actuation by providing an optimized pneumatic valve assembly.
A pneumatic riveter may include a jaw assembly configured to extend around a portion of an object through which a fastener is to be driven, a lever configured to be actuated to initiate rivet driving, a valve assembly portion comprising a piston configured to enable progressive control of rivet driving responsive to actuation of the lever, and an unlocking assembly. The unlocking assembly may be configured to selectively inhibit operation of the lever responsive to positioning of a button of the unlocking assembly in a locked position, and enable operation of the lever responsive to positioning of the button in an unlocked position.
Having thus described some example embodiments in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:
Some example embodiments now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all example embodiments are shown. Indeed, the examples described and pictured herein should not be construed as being limiting as to the scope, applicability or configuration of the present disclosure. Rather, these example embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like reference numerals refer to like elements throughout. Furthermore, as used herein, the term “or” is to be interpreted as a logical operator that results in true whenever one or more of its operands are true. As used herein, operable coupling should be understood to relate to direct or indirect connection that, in either case, enables functional interconnection of components that are operably coupled to each other.
As indicated above, some example embodiments may relate to the provision of a riveter that incorporates an improved safety interlock and an optimized pneumatic valve assembly.
As shown in
The riveter 100 includes a lever 120 (or actuator) that is provided on the riveter 100 to be actuated by a hand or finger of the operator when the riveter 100 is under positive control and the operator intends to drive a rivet in the direction shown by arrow 114. The lever 120 may be rotatable about its mounting axis and, in some cases, may also be movable along the axis. Rotation about the mounting axis may be used to actuate the pneumatic power source of the riveter 100 to drive a rivet in the direction of arrow 114. The movement along the axis (e.g., in the direction of arrow 114) may be used to position a flange 130 provided at a rear end of the lever 120 so that the flange 130 is clear of a safety interlock tab 140. Prior to movement of the lever 120 along the axis, the safety interlock tab 140 may block rotation of the flange 130 (preventing actuation). However, after movement of the lever 120 forward along the axis, the safety interlock tab 140 may be no longer aligned with the flange 130 so that the flange 130 can rotate when the lever 120 is rotated about the axis. The flange 130 may, when rotated, encounter and actuate a piston of a pneumatic valve assembly 150 of the riveter 100.
This structure, although effective, requires the operator to make sure that the lever 120 is positioned so that the flange 130 is clear of the safety interlock tab 140 to permit actuation. However, the safety interlock tab 140 is exposed and could be broken off to prevent this safety interlock from properly operating. Accordingly, the riveter 100 may be alternatively designed to include a lever 220 of an example embodiment, and a valve assembly portion 230 that has an improved unlocking assembly 240 in accordance with an example embodiment. A piston 232 of the valve assembly portion 230 may be configured to have improved geometries and allow increased control over the stroke of the piston 232 responsive to the provision of pneumatic power based on the amount or speed of application of pressure on the lever 220.
The unlocking assembly 240 may include an unlocking button, e.g. button 242. When the button 242 is in its rest position (or locked position), a blocking tab 250 may prevent the flange 226 from rotating to contact and displace the piston 232. The button 242 may be biased to the rest position by springs or other biasing members. In an example embodiment, one or more springs 243 may be provided around or between posts or screws 245 that connect the button 242 to a body or housing of the riveter 200. The springs 243, which are shown in the cross section view of
The button 242 and the blocking tab 250 are highlighted in context and shown from two different perspectives in
Accordingly, it should be appreciated that the unlocking assembly 240 may have a locked position and an unlocked position. While the unlocking assembly 240 is in the unlocked position, the blocking tab 250 is moved to allow rotation of the flange 226 to enable the flange 226 to contact the piston 232. Thereafter, the flange 226 is rotatable so that it can be “held” in a holding position from which subsequent actuation of the lever 220 is possible while the flange 226 prevents the blocking tab 250 from moving to place the unlocking assembly 240 in the locked position to enable subsequent operations of the lever 220 without corresponding operation of the button 242. As can be appreciated from
Thus, during operation, while the operator has positive control of the riveter 200, the operator will push slightly down on the operator portion 222 of the lever 220 to rotate the lever 220 slightly, e.g. a predetermined rotation amount, such as about 15 degrees. Simultaneously (or nearly so), the operator may push inwardly on the button 242 thereby moving the blocking tab 250 in the direction of arrow 252 to permit the flange 226 to contact the piston 232 when the lever 220 is rotated further by the operator. The button 242 can then be released, but the flange 226 will (as long as some small pressure is maintained by the operator) prevent the blocking tab 250 from moving back to the locked position. Rotation of the lever 220 thereafter will actuate the piston 232 progressively to start the riveting cycle and as long as the lever 220 is not completely released, the blocking tab 250 will not return to the locked position. This can allow the operator to initiate a number of sequential riveting operations without operating the button 242 again. If, however, the lever 220 is completely released, a spring 275 provided in the space below the piston 232 will return the piston 232 upward and also return the flange 226 to a position that allows the blocking tab 250 to move back into the position shown in
The above described unlocking assembly 240 and operation may be referred to as a two-step (2S) design. The operator may perform two steps to unlock the riveter for operation. The first step, e.g. depression of the button 242 may be performed substantially simultaneously with the second step of rotating the lever 222, as discussed above. In some example embodiments other unlocking assemblies may be provided including a three step design (3S), a four step design (4S), or the like, as described below. In an example embodiments, the unlocking assembly 240 may be a modular unit, which may be removed and replaced with other unlocking assemblies, e.g. a three step design or four step design.
The button 442 may be operably coupled to a blocking tab 450 configured to prevent a flange 426 from actuating a piston 432 to actuate a valve assembly portion 430, which in turn initiates rivet driving. As illustrated in
In some example embodiments, the unlocking assembly 440 or the valve assembly portion 430 may include a piston blocker 460. The piston blocker 460 may be configured to limit or prevent rotation of the flange 426 when the flange 426 is aligned with the piston blocker 460. In an example embodiment, the piston blocker 460 may be an extension of the valve assembly portion 430 adjacent to the piston 432, as depicted in
In an alternative embodiment depicted in
During or substantially simultaneously with step one, the operator may perform step two, e.g. translating the operator portion 422 of the lever 420 forwardly, as depicted by arrow 402, in the longitudinal direction of extension. Forward movement of the operator portion 422 of the lever 420 may cause the flange 426 to move forwardly, as depicted by arrow 406, to a permissive position. In an example embodiment, the forward movement of the flange 426 may cause the flange 426 to be positioned such that rotation of the flange 426 will not be obstructed by the piston blocker 460. Upon completion of step one, rotating the vertical extension 452 of the blocking tab 450, and step two, shifting the position of the flange 426 relative to the piston blocker 460, the operator portion 422 of the lever 420 may be rotated an additional amount, e.g. step three, to actuate the piston 432, thereby initiating rivet driving.
Turning to
While the flange 426 remains rotated at least the predetermined amount, e.g. about 15 degrees, which as discussed above may be referred to as a holding position, the flange 426 may be prevented from translating rearwadly by the piston blocker 460 and may prevent the vertical extension 452 of the blocking tab 450 from rotating between the flange 426 and the piston 432. As such, the subsequent actuation of the lever 420 to depress or actuate the piston 432 may be enabled without corresponding operation of the button 442 or forward translation of the lever 420.
When pressure is released from the operator portion 422 of the lever 420, the lever 420 and therefore the flange 426 may rotate to the release position, allowing the biasing element 443 associated with the button 442 to cause the blocking tab 452 to rotate to the blocking position corresponding to the locked position, as the guide rod 453 translate the deflection guide 454. As discussed above, in the blocking position the vertical extension 452 of the blocking tab 450 may prevent rotation of the flange 426. Additionally, the lever 420 and therefore flange 422 may translate reawardly to be blocked by the piston blocker 460.
The button 542 may include or be operably coupled to a biasing element 544, such as a coil spring. The biasing element 544 may be configured to bias the button 542 toward a blocking position corresponding to a locked position of the unlocking assembly 540. The biasing of the button 542 may be translated to the blocking tab 550 through the pivot cam 554, such that the biasing element 544 biases the blocking tab 550 toward the blocking position. The blocking tab 550 may be configured to prevent rotation of the flange 526, in the locked position, as discussed below in reference to
Similar, to the three step design, the lever 520 is biased rearwardly by a biasing element 528. The biasing element 528 may bias the lever 520 toward the lever lock position, in which the blocking projection 552 blocks rotation of the flange 526. As discussed above in reference to
The lever 520 may be configured to successively actuate the piston without subsequent operation of the button 542, while a pressure is maintained on the operator portion 522 in a holding position, e.g. the lever 520 is rotated at least the predetermined amount, such as about 15° and the lever 520 is translated forwardly to the permissive position. In the holding position, the flange 526 is rotated at least the predetermined amount preventing the blocking tab 550 from moving to the blocking position. Additionally, the lever 520 may be held in the permissive position by the operator to prevent the lever from translating rearwardly to the lever lock position. In some embodiments, the lever 520 may be translated rearwardly to the lever lock position, and then translated forwardly to the permissive position without the locking assembly 540, e.g. the holding tab 550 moving to the locked position, as long as the lever 520 is maintained rotated at least the predetermined amount.
At the completion of a riveting operation the operator may release the operator portion 522 of the lever enabling the lever 520 to rotate to a release position. The lever 520 may be biased toward the release position, e.g. non-rotated position by a bias element, such a spring substantially similar to spring 275, as discussed above in reference to
In an example embodiment, components may be removed from an unlocking assembly to change the number of steps utilized to unlock a riveter. In an example three step design, as discussed above in reference to
As discussed above, the unlocking assemblies 240, 440, and 540 may have a modular design, such that the unlocking assemblies 240, 440, and 540, and thereby number of unlocking steps, may be interchangeable based on the safety requirements of the job, site, or operator.
In some example embodiments, a lever of a riveter may be configured for operation by a first hand of an operator and a button may be configured for operation by a second hand of the operator. The lever and the button may be positioned on the riveter to prevent, or discourage, operation of the button and the lever by the same hand of the operator. The two hand operation to unlock the riveter may assist in ensuring positive control of the riveter prior to allowing rivet operations.
In some embodiments, the riveter may be further configured for optional modifications. In this regard, for example, in the unlocked position, a blocking tab of the unlocking assembly is moved to allow rotation of a flange disposed on the lever to enable the flange to contact the piston. In an example embodiment, the flange and the blocking tab are provided within a cover of the valve assembly portion. In some example embodiments, the blocking tab is laterally shifted from a first position to a second position corresponding to the locked position and the unlocked position of the unlocking assembly, respectively. In an example embodiment, the flange is rotatable to a holding position from which subsequent actuation of the lever is possible while the flange prevents the blocking tab from moving to place the unlocking assembly in the locked position to enable subsequent operations of the lever without corresponding operation of the button. In some example embodiments, the lever is biased toward a release position and the blocking tab is biased toward placing the unlocking assembly in the locked position, such that in the absence of pressure on the lever, the lever rotates to the release position enabling the blocking tab to move to place the unlocking assembly in the locked position. In an example embodiment, the blocking tab is rotated about an axis from a first position to a second position corresponding to the locked position and the unlocked position of the unlocking assembly, respectively. In some example embodiments, the flange is translated forwardly to a holding position from which subsequent actuation of the lever is possible while the flange prevents the blocking tab from moving to place the unlocking assembly in the locked position to enable subsequent operations of the lever without corresponding operation of the button. In an example embodiment, the lever is biased toward a release position and the blocking tab is biased toward placing the unlocking assembly in the locked position, such that in the absence of pressure on the lever, the lever rotates to the release position enabling the blocking tab to move to place the unlocking assembly in the locked position. In some example embodiments, the unlocking assembly includes a blocking tab which prevents rotation of a flange to actuate the piston in the locked position. In an example embodiment, the unlocking assembly also includes a pivot cam. The pivot cam includes a first end operably coupled to the button and a second end operably coupled to the blocking tab. The pivot cam is configured to rotate about a pivot disposed between the first end and the second end, such that positioning of the button of the unlocking assembly to the unlocked position causes the blocking tab to allow rotation of a flange disposed on the lever. In some example embodiments, the flange is rotatable to a holding position in which the flange prevents the blocking tab from moving to place the unlocking assembly in the locked position. In an example embodiment, the flange is rotated about 15 degrees to the holding position. In some example embodiments, the blocking tab includes a blocking projection preventing actuation of the valve in a lever lock position. The lever is configured to be translated forwardly in a longitudinal direction of extension of the pneumatic riveter from a lever lock position to a permissive position from which subsequent actuation of the lever causes the flange to contact the piston. In an example embodiment, the lever is biased toward a release position and the blocking tab is biased toward placing the unlocking assembly in the locked position, such that in the absence of pressure on the lever, the lever translates reawardly and rotates to the release position enabling the blocking tab to move to place the unlocking assembly in the locked position. In some example embodiments, the unlocking assembly is a modular unit. In an example embodiment, the button is configured to be operated by a first hand of an operator and the lever is configured to be operated by a second hand of the operator and the button and the lever are positioned to prevent operation of both the button and the lever by one hand of the operator. In some example embodiments, the unlocking assembly is disposed on the pneumatic riveter on an end opposite the jaw assembly. In an example embodiment, the lever includes a lever arm. The lever arm is at least partially disposed within a shaft in a body of the pneumatic riveter. In an example embodiment, the button is depressed in a longitudinal direction of extension of the pneumatic riveter or in a direction perpendicular to the longitudinal direction of extension of the pneumatic riveter.
Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Moreover, although the foregoing descriptions and the associated drawings describe exemplary embodiments in the context of certain exemplary combinations of elements and/or functions, it should be appreciated that different combinations of elements and/or functions may be provided by alternative embodiments without departing from the scope of the appended claims. In this regard, for example, different combinations of elements and/or functions than those explicitly described above are also contemplated as may be set forth in some of the appended claims. In cases where advantages, benefits or solutions to problems are described herein, it should be appreciated that such advantages, benefits and/or solutions may be applicable to some example embodiments, but not necessarily all example embodiments. Thus, any advantages, benefits or solutions described herein should not be thought of as being critical, required or essential to all embodiments or to that which is claimed herein. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
This application claims the benefit of U.S. Provisional Application No. 62/330,474 filed on May 2, 2016 the entire contents of which are hereby incorporated herein by reference.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2017/030488 | 5/2/2017 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62330474 | May 2016 | US |
