Movable lifting stand

Abstract

A movable lifting stand includes a roller holder having its lower side assembled with a roller. A gearbox secured on the topside of the roller holder, and a worm gear to be turned manually is horizontally disposed in the interior of the gearbox. A transmission rod is vertically inserted through the roller holder, having its upper end formed with a bevel gear to be inserted in the interior of the gearbox and engaged with the worm gear. The transmission rod has its lower portion formed with a threaded rod to be threadably combined with the upright plate of a combining base. The worm gear can be turned around with a manual tool to actuate the combining base together with a machine stable fixed thereon to move up and down so as to enable the machine table to be slidably moved around or positioned stably at a place

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a movable lifting stand, particularly to one to be set under a proper portion of a special machine table for propping up the machine, able to be adjusted to lift the machine table for facilitating the machine table to be moved around.

2. Description of the Prior Art

Most medium-sized and small-sized processing machines, such as planing machines and emery-grinding machines, are respectively provided with a support base frame under a machine table for supporting the machine table. Nevertheless, the support base frame is provided with no rollers; therefore, when the machine table needs to be transferred to different locations, it always has to be moved manually, wasting much time and labor. To improve this drawback, rollers with brakes are assembled under the support base frame for supporting and controlling the machine table to be slidably moved around or fixed stably at a place.

However, since the medium-sized and the small-sized machine tables are pretty heavy; therefore, the rollers assembled under the support base frame are likely to be damaged after used for a period of time. In addition, common rollers can hardly be fixed in position; therefore, the machine table may swing together with the unstable rollers, thus affecting precision and quality of processing in carrying out processing.

SUMMARY OF THE INVENTION

The objective of the invention is to offer a movable lifting stand including a roller holder, a gear box, a worm gear, a transmission rod and a combining base. The gearbox is secured on the topside of the roller holder, and the worm gear able to be turned manually is horizontally positioned in the interior of the gearbox. The transmission rod vertically inserted through the roller holder has its upper end formed with a bevel gear to be inserted in the interior of the gear box and engaged with the worm gear and its lower portion formed with a threaded rod to be threadably combined with the combining base. The worm gear can be turned with a manual tool to actuate the combining base to move up and down. Thus, when a special machine table is fixed on the combining bases of plural movable lifting stands, it can be moved up and down together with the combining bases, facilitating the machine table to be stably fixed at a place or slidably moved around.

BRIEF DESCRIPTION OF DRAWINGS

This invention will be better understood by referring to the accompanying drawings, wherein:

FIG. 1 is a perspective view of a first preferred embodiment of a movable lifting stand in the present invention;

FIG. 2 is an exploded perspective view of the first preferred embodiment of the movable lifting stand in the present invention;

FIG. 3 is a partial side cross-sectional view of the first preferred embodiment of the movable lifting stand in the present invention;

FIG. 4 is another partial side cross-sectional view of the first preferred embodiment of the movable lifting stand in the present invention;

FIG. 5 is a side cross-sectional view of the first preferred embodiment of the movable lifting stand being adjusted to move up and down in the present invention;

FIG. 6 is an exploded perspective view of a second preferred embodiment of a movable lifting stand in the present invention; and

FIG. 7 is an exploded perspective view of a third preferred embodiment of a movable lifting stand in the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A first preferred embodiment of a movable lifting stand in the present invention, as shown in FIGS. 1 and 2, includes a roller holder 10, a gear box 20, a worm gear 30, a transmission rod 40 and a combining base 50 as main components combined together.

The roller holder 10 is formed with an inverted L-shaped frame body 11 having one side of its top plate 111 vertically and axially combined with a rotatable roller supporter 12 having a roller 121 fitted thereon and a braking plate 122 assembled at a proper location for stopping the roller 121 from sliding. The top plate 111 of the frame body 11 is bored with two threaded holes 112 and a through hole 113 at proper locations. The frame body 11 is further provided at the lower side with a horizontal support plate 114 extending outward and having a shaft hole 115 aligned to the through hole 113 of the top plate 111.

The gear box 20 consists of a lower casing 21 and an upper cover 22 able to be combined together to form an accommodating space 23 in the interior. The lower casing 21 and the upper cover 22 have their opposite sides respectively cut with an arc-shaped clamping notch 211, 221 able to be combined to form a shaft hole 24 after the upper cover 22 and the lower casing 21 are correspondingly combined together. The lower casing 21 has it lower side bored with a through slot 212. The lower casing 21 and the upper cover 22 have their opposite sides respectively bored with a vertical insert hole 213, 222 aligned to each other for bolts 25 to be respectively inserted therethrough and then screwed with the two threaded holes 112 of the top plate 111 so as to fix the gear box 20 on the top plate 111 of the roller holder 10.

The worm gear 30 is horizontally received in the accommodating space 23 of the gear box 20, having its opposite ends fitted with the opposite shaft holes 24 of the gear box 20. The worm gear 30 has one end formed with a driving portion 31 (being a hexagonal bolt groove in this preferred embodiment) for the hexagonal bolt head of a manual or an electric tool to be engaged therein and turned around for carrying out adjustment of the worm gear 30.

The transmission rod 40 is vertically inserted downward through the through hole 113 of the top plate 111 and the shaft hole 115 of the support frame 114 of the roller holder 10. The transmission rod 40 has its upper end formed with a bevel gear 41 to be inserted in the accommodating space 23 of the gear box 20 through the bottom through slot 212 of the lower casing 21 and engaged with the worm gear 30 in the gear box 20. The transmission rod 40 further has its lower portion formed with a threaded rod 42.

The combining base 50 is composed of an upright plate 51 and horizontal support plate 52. The upright plate 51 has its outer side fixed oppositely with an upper and a lower combining plate 511 extending out horizontally at proper locations to be set under the roller holder 10. The two combining plates 511 are respectively bored with a threaded hole 512 to be screwed with the threaded rod 42 of the transmission rod 40. The support plate 52 extends inward horizontally from the bottom edge of the upright plate 51, having its opposite sides respectively bored with a transverse position-limiting slot 521. Further, the upright plate 51 of the combining base 50 has the opposite lower edges opposite to the two position-limiting grooves 521 of the support plate 52 respectively formed with a lug 514 extending downward and having an insert hole 513 for an adjusting threaded rod 53 to be inserted therethrough and extend along the position-limiting slot 521. A holding plate 54 to be fitted on the support plate 52 has its opposite lower edges respectively formed with a fixing lug 542 extending downward and having a threaded hole 541. The two fixing lugs 542 of the holding plate 54 are respectively inserted downward through the two position-limiting slots 521 of the support plate 52 to be respectively screwed with the two adjusting threaded rods 53. Thus, the holding plate 54 can be actuated by the two adjusting threaded rods 53 to be restricted and moved transversely along the two position-limiting slots 521 for holding stably the bottom side of the machine table 60. Furthermore, a plate-shaped magnet 55 is provided to magnetically sucking the inner wall of the upright plate 51 and also for magnetically sucking the wall of the machine table 60 to secure it stably.

A second preferred embodiment of a movable lifting stand in the present invention, as shown in FIG. 6 has a structure almost the same as that described in the first preferred embodiment, except that the frame body 11 of the roller holder 10 is shaped as a rectangular body having the opposite sides of its top plate 111 respectively extending downward and forming a side plate 116. A stationary roller 13 is fixed between the two side plates 116, and a braking plate 14 is disposed at the inner side of the top plate 111 for stopping the roller 13 from sliding.

The difference between the first and the second preferred embodiment of the movable lifting stand is that the roller 121 provided in the first preferred embodiment is rotatable, while the roller 13 provided in the second preferred embodiment is stationary; therefore, a user has options to choose a proper-typed movable lifting stand in advance. In general, a movable lifting stand provided with two rotatable rollers 121 and two stationary rollers 13 are commonly employed.

In assembling and using, as shown in FIGS. 1 and 3, firstly, the combining bases 50 of the movable lifting stands are set under the support base frame 61 at the underside of a preset machine table 60 and combined with the corresponding wall of the machine table 60 by magnetic attraction of the plate magnet 55 on the inner side of the upright plate 51, letting the support plate 52 of the combining base 50 support the underside of the support base frame 61. Next, the adjusting threaded rods 53 are properly turned to actuate the holding plate 54 to move outward and hold tight the inner side plate 611 of the support base frame 61 to let the combining base 50 fixed with the support base frame 61. Subsequently, the worm gear 30 is turned around by a proper manual tool to actuate the transmission rod 40 to rotate and move up the combining base 50, which is threadably assembled on the transmission rod 40, and simultaneously prop up the machine table 60 on the combining base 50 to let the support base frame 61 moved away from the ground. Thus, the machine table 60 on the combining base 50 can be slidably moved around by means of the rollers 121, 13 of the movably lifting stand or fixed in place by means of the braking plates 122, 14 on the roller bases 10 to prevent the machine table 60 from sliding to move about randomly.

After the machine table 60 is slidably transferred to a proper location, the combining base 50 together with the machine table 60 at that position can be lowered down to let the support base frame 61 stand stably on the ground and support the machine table 60 to facilitate the machine table 60 to operate and carry out processing steadily and smoothly.

A third preferred embodiment of a movable lifting stand in the present invention, as shown in FIG. 7, has a structure almost the same as that described in the first preferred embodiment, except that the upright plate 5 of the combining base 50 is bored with a plurality of insert holes 515 for locking bolts 516 to be respectively inserted therethrough and secured with the corresponding wall of a machine table 60 and the worm gear 0 has its driving portion 31 formed with a hexagonal bolt to be engaged with the hexagonal bolt groove of a manual or an electric tool (not shown) so that the manual or the electric tool can be pulled to turn around the worm gear 30.

Specifically to say, the movable lifting stand of this invention can be easily combined with a special machine table 60, and the machine table 60 on the movable lifting stand can be moved up and down by turning around the worm gear 30 and slidably moved about by means of the rollers 121, 13 of the movable lifting stand, convenient in shifting the machine table 60.

While the preferred embodiments of the invention have been described above, it will be recognized and understood that various modifications may be made therein and the appended claims are intended to cover all such modifications that may fall within the spirit and scope of the invention.

Claims

1. A movable lifting stand comprising:

A roller holder having its lower side assembled with a roller;

A gearbox firmly fixed on the top plate of said roller holder, said gearbox formed with an accommodating space in the interior;

A worm gear horizontally received in said accommodating space of said gear box, said worm gear having one end formed with a driving portion for turning said worm gear;

A transmission rod vertically inserted through said roller holder and having its upper end formed with a bevel gear to be positioned in the interior of said gear box, said bevel gear engaged with said worm gear in said gear box, said transmission rod further having its lower portion formed with a threaded rod; and

A combining base having a proper portion threadably combined with said threaded rod of said transmission rod, said combining base able to be actuated to move up and down by rotation of said transmission rod.

2. The movable lifting stand as claimed in claim 1, wherein said combining base is formed with an upright plate having its outer wall fixed oppositely with an upper and a lower combining plate extending out horizontally to be set under said roller holder, said two combining plates respectively bored with a threaded hole to be screwed with said threaded rod of said transmission rod.

3. The movable lifting stand as claimed in claim 2, wherein said upright plate of said combining base is bored with a plurality of insert holes respectively for a locking bolt to be inserted therethrough and locked with the corresponding side of a preset machine table.

4. The movable lifting stand as claimed in claim 2, wherein said upright plate has its lower edge extending inward horizontally and forming a support plate having its opposite sides respectively bored with a transverse position-limiting slot, said upright plate having its opposite lower edges respectively formed with a lug extending downward at the location corresponding to said position-limiting slot, said two lugs respectively bored with an insert hole for an adjusting threaded rod to be inserted therethrough and extend along said position-limiting slot, a holding plate fitted on said support plate, said holding plate having its opposite lower edges respectively formed with a fixing lug extending downward, said two fixing lugs of said holding plate respectively inserted downward through said two position-limiting slots to be screwed with said two adjusting threaded rods, said holding plate actuated to move transversely along said two position-limiting slots of said support plate when said two adjusting threaded rods are turned around, said holding plate moved outward to support the bottom of a machine table.

5. The movable lifting stand as claimed in claim 4, wherein said vertical plate of said combing base has its inner side combined with a plate magnet to suck stably the corresponding wall of said machine table supported on said combining base.

6. The movable lifting stand as claimed in claim 1, wherein said gear box consists of a lower casing and an upper cover, said lower casing and said upper cover having their opposite sides respectively cut with an arc-shaped clamping notch aligned to each other, said arc-shaped clamping notches of said lower casing and said upper cover combined to form a shaft hole after said lower casing and said upper cover are correspondingly combined together, said shaft hole axially positioning the opposite ends of said worm gear, said lower casing having its bottom bored with a through slot for the upper end of said transmission rod to be inserted therethrough, said lower casing and said upper cover having their opposite sides respectively bored with a vertical insert hole aligned to each other, bolts respectively inserted through said vertical insert holes to secure said gear box on the top plate of said roller holder.

7. The movable lifting stand as claimed in claim 1, wherein said top plate of said roller holder has a proper portion vertically and pivotally fitted with a rotatable roller supporter provided thereon with a braking plate for stopping said roller from sliding.

8. The movable lifting stand as claimed in claim 1, wherein said top plate of said roller holder has the opposite sides respectively extending downward and forming a side plate, with a roller assembled between said two side plates, a braking plate fixed at the inner side of said top plate of said roller holder for stopping said roller from sliding.

9. The movable lifting stand as claimed in claim 1, wherein said driving portion of said worm gear is a hexagonal bolt groove.

10. The movable lifting stand as claimed in claim 1, wherein said driving portion of said worm gear is a hexagonal bolt.