Foldable stand for a machine

A foldable stand for supporting a machine can be folded or extended between a collapsed position, an extended supporting position, and a hand carrying position. The foldable stand includes a platform formed by two bearing bars that define a bearing surface for supporting a machine. Two support units are pivotally connected to the bearing bars and can be pivoted, and selectively locked, between a collapsed position, an extended supporting position, and a hand carrying position. The selective locking is achieved by the selective engagement of positioning devices with locating grooves formed on the foldable stand.

FIELD OF THE INVENTION

The present invention relates to machine stands and more particularly, to a foldable stand for supporting a machine, which can be collapsed rapidly and which facilitates movement of the machine to different locations.

BACKGROUND

Taiwan Patent Publication Number M273664 discloses a foldable tool stand, which includes a table, a first leg and a second leg respectively pivotally connected to the table, and a locking mechanism. The locking mechanism comprises four first locating members set between the table and the legs, and right and left second locating members, wherein each first locating member has a rod-like shank, a stop portion extending from the periphery of the rod-like shank and a finger strip extending from the periphery of the rod-like shank. The rod-like shank of each first locating member is pivotally connected to the table by a pivot such that the user can manipulate the finger strip to rotate the rod-like shank of each of the first locating members, moving the stop portions to abut against the legs, thereby locking the legs in the extended position. Further, the right and left second locating members are respectively located on the table for securing the legs in the collapsed position.

While this design is functional, there is room for improvement. According to the aforesaid design, the first locating members are installed in the legs. In order to collapse the foldable tool stand, the user must manipulate the finger strip of each first locating member to rotate the rod-like shank of each first locating member counter-clockwise, thus disengaging the stop portions away from the legs for enabling the legs to be turned to the collapsed position. This procedure is complicated. Further, the left second locating member is a curved spring plate fixedly provided at the table. After a long period of use in abutment against the second leg, the left second locating member will deform, and will thus decrease the effectiveness thereof. Accordingly, at least an improvement on the design of the left second locating member is deemed necessary.

SUMMARY

The present disclosure has been accomplished under the circumstances in view. One feature of the present disclosure is to provide a foldable stand, which can be easily set in an extended supporting position for supporting a machine, a collapsed position, or a hand-carrying position for moving the machine to another location.

Thus, the foldable stand according to the present disclosure includes two bearing bars, two support units, a plurality of locating grooves, and two positioning devices. The bearing bars are arranged generally in parallel, and define a bearing surface for carrying a machine. The support units have the respective top sides thereof respectively pivotally connected to the distal ends of the bearing bars. The locating grooves are respectively located at the ends of the bearing bars. The positioning devices are respectively arranged in the support units and movable between two positions. When the positioning devices are moved to the first position, the support units are engaged in the locating grooves and locked to the bearing bars in the extended, collapsed or hand-carrying position. When the positioning devices are moved to the second position, the support units are movable relative to the bearing bars between the respective locating grooves.

Thus, the operation of the foldable stand of the present disclosure is simplified, thus facilitating working convenience. Further, because the second support unit can be used as a handlebar, the cost of an extra handlebar is eliminated.

DETAILED DESCRIPTION

Referring toFIGS. 1-3, a foldable stand10is shown having a bearing unit20, a first support unit30, a second support unit40, a set of locating grooves50, and a positioning device set60.

The bearing unit20defines a platform having a first lateral side and a second lateral side opposed thereto, and being formed by two rectangular members, i.e., a front bearing bar202and a rear bearing bar204, that are spaced from each other at a predetermined distance and arranged generally in a parallel manner. The bearing unit20defines a bearing surface for supporting a machine (not shown), such as, for example, a table saw, miter saw, scroll saw, band saw, drilling machine, sander or the like. The front bearing bar202and the rear bearing bar204each have a first through hole206disposed at a first, left end, a lug208downwardly extended from a second, right end, and a second through hole210transversely defined through the lug208. The rear bearing bar204has an angled hook member24pivotally connected thereto. The angled hook member24has one end terminating in a handle242and the other end terminating in a hook portion244.

The first support unit30includes a front leg302and a rear leg304arranged generally in parallel, a stretcher32connected between the front leg302and the rear leg304, and a first protruding device34formed of a screw and pivotally connected to the rear leg302. Two wheel brackets36are respectively fixedly fastened to the front leg302and the rear leg304near a first, top end of the respective leg that is adjacent to the bearing surface of the bearing unit20. Two wheels362are respectively pivotally mounted on the wheel brackets36. Two oblong slots306are respectively transversely defined through the front leg302and the rear leg304near the top end of the respective leg.

The second support unit40includes a front leg402and a rear leg404arranged generally in parallel, a stretcher42connected between the front leg402and the rear leg404, and two oblong slots406respectively transversely defined through the front leg402and the rear leg404near the first, top end of the respective leg. Each of the oblong slots306,406has a smooth arcuate top side and a smooth arcuate bottom side.

Further, as shown inFIG. 2andFIGS. 1,4,5and6, four screw bolts212are respectively inserted through the first through holes206and second through holes210and the top ends of the legs302,304,402and404to pivotally connect the legs302and304of the first support unit30to the first, left ends of the bearing bar202and204of the bearing unit20and the legs402and404of the second support unit40to the second, right ends of the bearing bar202and204of the bearing unit20, enabling the first support unit30and the second support unit40to be respectively moved relative to the bearing unit20to an extended position (seeFIG. 1), a collapsed position (seeFIGS. 4 and 5), or a hand-carrying position (seeFIG. 6).

As illustrated inFIG. 5, the lugs208extend downwards from the second, right ends of the bearing bars202and204. The distance between the second through holes210and the bearing surface of the bearing unit20is relatively greater than the distance between the first through holes206and the bearing surface of the bearing unit20. Thus, when the first support unit30and the second support unit40are moved to the collapsed position, the first support unit30is disposed at the top side of the second support unit40without interfering with the collapsing of the second support unit40.

The locating grooves50(seeFIG. 3) include two first locating grooves502respectively located on the bottom edges of the left ends of the front bearing bar202and rear bearing bar204of the bearing unit20right below the first through holes206. Two second locating grooves504are respectively located on the bottom edges of the left ends of the front bearing bar202and rear bearing bar204of the bearing unit20at a right side relative to the first through holes206. Two third locating grooves506are respectively located on the bottom edges of the lugs208of the front bearing bar202and rear bearing bar204of the bearing unit20at the left side relative to the second through holes210. Two fourth locating grooves508are respectively located on the bottom edges of the lugs208of the front bearing bar202and rear bearing bar204of the bearing unit20below the second through holes210. Two fifth locating grooves510are respectively located on the bottom edges of the lugs208of the front bearing bar202and rear bearing bar204of the bearing unit20at the right side relative to the second through holes210. Each of the locating grooves502,504,506,508, and510are formed as smooth arcuate portions.

When the first support unit30is moved to the extended position, the two oblong slots306are respectively aligned with the two first locating grooves502. When the first support unit30is moved to the collapsed position, the two oblong slots306are respectively aligned with the two second locating grooves504. When the second support unit40is moved to the extended position, the two oblong slots406are respectively aligned with the two fourth locating grooves508. When the second support unit40is moved to the collapsed position, the two oblong slots406are respectively aligned with the two third locating grooves506. When the second support unit40is moved to the hand-carrying position, the two oblong slots406are respectively aligned with the two fifth locating grooves510. The border edges of the bearing unit20between the first locating grooves502and the second locating grooves504, the border edges of the bearing unit20between the third locating grooves506and the fourth locating grooves508, and the border edges of the bearing unit20between the fourth locating grooves508and the fifth locating grooves510are arcuate, forming first smoothly arcuate edges52, second smoothly arcuate edges54and third smoothly arcuate edges56respectively.

The positioning device set60comprises a first round rod602inserted through the two oblong slots306of the first support unit30, a second round rod604inserted through the two oblong slots406of the second support unit40, four pins606, four tensile springs608and four knobs610. The two distal ends of each of the first and second round rods602and604are threaded. After insertion of the round rods602and604through the oblong slots306and406of the support units30and40, the knobs610are respectively threaded onto the threaded ends of the round rods602and604to prevent inadvertent removal of the round rods602and604from the oblong slots306and406. The pins606are respectively fixedly mounted in the top ends of the legs302,304,402and404above the respective oblong slots306and406. The tensile springs608have their respective top ends respectively connected to the pins606and their respective bottom ends respectively connected to the round rods602and604.

As shown inFIGS. 7 and 8, the round rods602and604are normally held in the oblong slots306and406in a first position (seeFIG. 7) when they receive no external force. A force can be applied to the round rods602and604to move the round rods602and604downwards along the oblong slots306and406to a second position (seeFIG. 8). When the external force is released from the round rods602and604, the tensile springs608pull the round rods602and604back to the first position.

Referring toFIG. 9, when the user wishes to collapse the foldable stand10, the first round rod602is moved downwards along the oblong slots306from the first position to the second position and then the first support unit30is pivoted to move the first round rod602out of the first locating grooves502and along the first smoothly arcuate edges52to the second locating grooves504. After the first round rod602has been engaged into the second locating grooves504, the handle242of the angled hook member24is moved to hook the hook portion244on the first protruding device34(seeFIG. 9), thereby locking the first support unit30in the collapsed position (seeFIG. 4). Thereafter, the second round rod604is moved downwards along the along the oblong slots406from the first position to the second position and then the second support unit40is pivoted to move the second round rod604out of the fourth locating grooves508and along the second smoothly arcuate edges54to the third locating grooves506. After the second round rod604has been engaged into the third locating grooves506, the second support unit40is locked in the collapsed position (seeFIG. 5).

When the user wishes to extend out the foldable stand10, the second round rod604is moved along the oblong slots406from the first position to the second position and then the second support unit40is pivoted to move the second round rod604out of the third locating grooves506and along the second smoothly arcuate edges54to the fourth locating grooves508to set the second support unit40in the extended position (seeFIG. 4). Thereafter, the handle242of the angled hook member24is moved to disengage the hook portion244from the first protruding device34of the legs304, and then the first round rod602is moved downwards along the oblong slots306from the first position to the second position and then the first support unit30is pivoted to move the first round rod602out of the second locating grooves504and along the first smoothly arcuate edges52to the first locating grooves502, thereby locking the first support unit30in the extended position (seeFIG. 1).

In order to enhance stability of the support units30and40in the extended position, as shown inFIG. 10, two locking bars26and27are provided at the bearing unit20, and a second protruding device38and a third protruding device44are respectively provided at the support units30and40. The arrangement of the locking bars26and27and the protruding devices38and44may be variously embodied. According to the present preferred embodiment, the locking bars26and27are respectively pivotally connected to the two ends of the rear bearing bar204. One locking bar26has a handle262and a retaining notch264. The other locking bar27has a handle272and two retaining notches274and276.

The second protruding device38and the third protruding device44are respectively pivotally connected to the top ends of the rear legs304and404. When the first support unit30is moved to the extended position, the handle262of the locking bar26is moved to force the retaining notch264into engagement with the second protruding device38at the rear leg304, thus locking the first support unit30in the extended position. When the second support unit40is moved to the extended position, the handle272of the locking bar27is moved to force the retaining notch274into engagement with the third protruding device44at the rear leg404, thus locking the second support unit40in the extended position. Similarly, the user can move the handles262and272of the locking bars26and27to disengage the retaining notches264and274from the second and third protruding device38and44.

When the user wishes to use the foldable stand10to move the loaded machine to an alternate location, the first support unit30is set in the collapsed position (seeFIG. 4), and then the second round rod604is moved downwards along the oblong slots406from the first position to the second position. Next, the second support unit40is pivoted to move the second round rod604out of the fourth locating grooves508and along the third smoothly arcuate edges56to the fifth locating grooves510to lock the second support unit40in the hand-carrying position (seeFIG. 6).

To enhance the positioning, the handle272of the locking bar27is moved to force the retaining notch276of the locking bar27into engagement with the third protruding device44at the rear leg404(seeFIG. 11). Thus, the user can use the second support unit40as the handlebar of the foldable stand10to move the wheels362of the first support unit30along the floor, thereby moving the loaded machine to the desired location.

By means of moving the positioning device set60, the support units are shifted among the respective locating grooves to lock the foldable stand in the extended, collapsed or hand-carrying position. Thus, the operation of the foldable stand of the present invention is simplified for facilitating working convenience. Further, because the second support unit can be used as a handlebar, the cost of an extra handlebar is eliminated.

An exemplary embodiment of a foldable stand has been constructed with the features ofFIGS. 1-11. The foldable stand functions smoothly to provide all of the features disclosed earlier.