GB2416801A

GB2416801A - Height adjustable support foot for a ladder, furniture, machine etc.

Info

Publication number: GB2416801A
Application number: GB0417196A
Authority: GB
Inventors: Shih-Yi Huang
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-08-02
Filing date: 2004-08-02
Publication date: 2006-02-08
Also published as: GB0417196D0

Abstract

A foot comprises a support post having a base (12) with a screw axle (11) mounted thereon, a plurality of retaining plates (2) with screw threaded inner surfaces which can engage the axle, a retaining cylinder (3) receiving the axle and retaining plates, the retaining cylinder having a plurality of apertures (314) which receive bearings (315), a control ring (32) surrounds the cylinder and an actuator (34) moves the control ring from a first position in which the bearings press upon the retaining plates, against a bias, to contact the axle and a second position (Figure 4) where the retaining plates are biased away from the axle.

Description

241 6801 AD,IVSTABLE SUPPORT FOoT Flee present invention relates to ad

justable support fools. and more particular!\ to an ad Instable support foot mounted beneath a stepladder. a frame structure. a piece of furniture or a machine so that the height thereof can be adjusted to maintain stabilit! The put-pose of an ad; ustable support foot of the prior art mounted untler a stepladder. a frame structure. a piece of furniture or a machine is for maintaining balance of the object thereon It mainly includes a support pad and a bolt device above the foot The bottom of an ob ject a stepladder. a frame structure. a piece of furniture or a machine. is provided \vith a plurality of ad instable support fools \hicl1 are secured within corresponding screw holes thereon To adjust the height of the support fools.

some of the support pads have to be rotated. hick is rather time 1 consuming For a user \\ho needs to shift a stepladder or a frame structure around during operation. the adjustment of the conventional support fools appears rather inconvenient.

especially wilen the stepladder or the frame structure is used on a rugged and rougl1 ground. Therefore. adjustable support fools of the prior art comprising a support pad and a bolt device cannot meet the requirement of promoting \vork efficiency.

Accordingly. the primary objective of the present invention is to provide an adjustable support foot whose height can be quickly adjusted. The adjustable support foot may comprise a 2 support post, a plurality of retaining plates, a control device and an outer shell. The support post may be a cylindrical body provided with a screwed axle in its upper section and a Cup base in its lo\\er section. lhe retaining plates are provided \\ ith sore\\ threads on the inner surfaces thereof. The scre\\ed axle is covered by the retaining plates. and then enclosed \\ithin a control de\ice that includes a retaining c! finder and u control ring. The control de\ ice can decouple the retaining plates Irom the scre\\ed axle or reengage them together. An outer shell may further enclose the control device. Thereby, the height of the adjustable support foot thus formed can be quickly adjusted.

The secondary objective of the present invention is to provide an adjustable support foot wherein the number of the retaining plates engaged \\ ith the screened axle can be two or more than t\\o.

The various objects and advantages of the present invention will be more readily understood from the following detailed description \\hen read in conjunction with the appended dra\vings Fig. I is a perspective v de\\ of an adjustable support foot according to the present invention.

Fig.2 is an exploded perspective view of an adjustable support foot according to the present invention.

Fig.3 is a cross-sectional view of an adjustable support foot according to the present invention wherein the retaining plates and the screwed axle are engaged.

Fig] is a cross-sectional vie\ of an adjustable support foot according to the present invention wherein the retaining plates and the screwed axle are decoupled.

Fig.5 illustrates a plurality of adjustable support fools according to the present invention mounted beneath the feet of a stepladder.

Refe'-riTlg to Fig 1 atoll 2. a', ad juslabic support foot accord',<' to the present intention comprises a support post 1. a pluralit! ol retaining plates 2. a control device 3 and an outer shell 4.

As SllO\\TT iT1 Fi=. I. tile upper portion of tile support post 1 is pro\ ided Fitly u scrc\\ed axle 1 1. and the lo\ver portToTl ol the StTppOrt post 1 is provided witl1 a Cup base 12. The axis at the cup base 12 can be fiXeLT OT of carda'1 shaft.

As ShO\T1 in 1 ig.2. the retaiTliTlg plates 2 are elongatecl plates arced in the transs erse direction. The inter wall of each of the retaining plates 2 is provided with a screw thread 21 capable of being engaged \\ ith the scre\ved axle 1 1. The outer \vall of each of the retaining plates 2 is provided with at least one scre\v hole 22.

A tapered surface 23 is formed on a lateral side of the outer \vall of each of the retaining plates. The looser T iTll of each of the retaining plates 2 is provided with a flange 25 having a taperer' surface 24. by \\hicl1 the screw thread 21 thereof can be engaged or decouples' with the screwed axle 11.

As shown in Fig.2 and 3. the control device 3 comprises a retaining cylinder 31. a control ring 32, a spring 33. an axial actuator 34 and a radial actuator 35. The lateral cross-section of the retaining cylinde'31 is T-shaped and hollow along the axial direction. l he bottom end of the retaining cylinder 31 is provided \ith a receiving hole 311 and the innermost end of the receive hole 311 is provided with an axial hole 312 going througl1 the upper portion of the retaining cylinder 31 iT1 the axial direction.

Bet\veen the receiv Tng hole 311 and the axial hole 312. there forms a tapered section 313 {he outer wall of the retainin, cylinder 2 I are further pro\icled with at least t\vo conic holes 314 \\hich are tapered in\\ardl! to connect the receiving hole 311 \vithn the retaining c, linger 31. F.ach of the conic holes 314 can house a steel ball 31:. the inner portion of \\ hick extends into the recoin ins hole 311. The control ring 32 is substantial!! a ring hod!. the inner \\all of \\hcl1 is provided with a groo\e '21 corresponding to the conic holes 314. The \vall of the control ring 32 Is further pro\idecl \\ith a plurality of slots 322 for restricting 1() the steel balls 315 in the Connie holes 314 and confining the control ring 32 to attach around the retaining cylinder 31. The spring 33 is located in the upper section of the retaining cylinder 31 lor rrUin1 a do\n\\ard force on the control ring 32. On the other hand.

the upper end of the spring 33 presses against an upper flange of IS the retaining cylinder 31. so that the control ring 32 tends to situate at the lo\ver end of the retainin. cylinder 31. The axial actuator 34 consists of a plurality of screws 341 uniformly nounted around the outer wall of the control ring 32 and a plurality of steel slings 342 each connected to a screw 341. As sho\n in Fig3. the steel slings 342 urge the control ring 32 to ele\ ate by \vhich the steel balls 315 fat] into the groove 321 on the inner wall of the control ring 32. The radial actuator 35 includes a plurality of scre\vs 351 each further including an elastic member 352 (suel1 as a spring) and a spacer 353. The sere\s 3SI S of the radial actuator 35 are inseited around the control ring 32.

through the slots 322 thereof and the outer shell 4.

As sho\vn in Fig.4. the outer shell 4 is a hollo\v shell body enclosing the control de\ice 3. \\hich comprises a lateral \\all 41.

an tipper cover 42 and a lo\ver cover 43. The upper and lover ends of the lateral \\ all 41 are respectively pr ovicled \\ ith an outer screw thread 41 I fur cngain<' with the upper cower 42 anti tht lo\\ er co\ er. I he lateral w all 41 is further provided \\ ith a pi ur alit! ol throng h holes 412 for receiving the scre\vs 31 of the radial actuator 3 as. {he througl1 holes 412 situate at selecletl places around the lateral \\all 41. corresponding to the slots 322 on the control ring 32. The inner wall of the upper eo\er 42 Is a cap body of U-shaped cross-section and is provided with an inner sore\\ threatl 421. The top surface of the upper cover 42 further nclutles an axial hole 422 and at least t\o through holes 423 for passing the steel sling 342. The inner wall of the lower cover 43 is a cap body of -shaped cross-section and is provided faith an 1 inner sore\\ thread 431. The bottom surface of the lover co\er 43 lurtiler includes on axial hole 432. The upper section of the axial hole 432 forms a conic portion 433 hating an inner wall tapered Up\\ arc.

Referring to Fig. I and 3. at least two retaining plates 2 (in this preferred embodiment. three retaining plates 2) are used to retain the screwed axle 11 of the support post 1. The retaining plates 2 are further applied with the retaining cylinder 31 and the receiving hole 311 of the control device 3. The outer shell is then used to enclose the control device 3. whereby the screened axle 11 goes througl1 axial holes 312.422 and 432 and the tapered surfaces 23 thereof are engaged witl1 the tapered section 313 and the flanges 25 thereof are secured in the conic portion 433 of the lo\\er co\er 43. Ihe scre\\s 31 of the radial actuator 35 on the control device 3 floes through the through holes 412 of the lateral \\all 41. the slots 322 of the control ring 32 and the rclainin cylinder 31. eventually being secured in the scre\v holes 22 oi the retaining plates 2. The elastic members 352 and the spacers 33 tend to pull the retaining. plates 2 out\vard. I he steel slings 342 ot the axial actuator 34. Cooing through the through holes 43 of the upper co\ er 4? can kc controlled from outside to move the control ring 32 along the screwed axle I]. T hereby. the adjustable support foot has the function of quickly ad lusting the height thereof Referring to Fig.3. to use the present invention. the control ring 32 is pushed do\\nard by the spring 33 so that the steel balls 315 are shifted in\\ard to support against the outer walls of the retaining plates 2. \vhereb the retaining plates 2 are driven 1 n\ard to almost encage the scre\\ed axle 11. The self gra\t! ot the object the adjustable support foot supports presses the outer shell 4 and the retaining cs finder 31 of the control device 3 down\\ai-d. whereas the retaining plates 2 move upward and the upper tapered surfaces 23 and the 1o\ver tapered surfaces 24 thereof respectively engage the tapered section 313 of the retainin; cviintler 31 and the conic portion 433 of the outer shell 4. Thereby. the retaining plates 2 shift inward again to engage the screwed axle 11. and the height of the support post I is fixed. It is a further function that the height of the support post I can he mildly adjusted to maintain stability. Referring to Fig.4. to tiuickl! elevate the support post 1. the steel slings 342 are pulled to urge the control ring 32 moving upward. whereby the groove If] on the inner \all thereofn1a! alien \\ith the steel halls 315 so that the steel halls 'I 5 depart from form the retainin', plates to drop In the grog\ c 321 I he elastic force applied b! radial actuator 35 then pulls the retaining plates 2 a\\ a! troth the scre\ed axle 11. anti theeforc the support post 1 can mO\C freer! After the height ad justment. the above procedure can be appletl again to secure the support post] Iherefore. ad justable support toots according to the present invention can be \'del! applied to the bottom surface of a 1() steplacicler. a lrane structure a piece of furniture or a macl1ine so that the height thereof can be quickly adjusted to maintain stability. particular!! suiting an ob ject that needs to shift around As sho\vn in Fi=.5. a plurality of adjustable support foots are mounted on the bottom of a stepladder 10. and the steel slings 342 thereof are guided to a proper location in the upper portion of the stepladder 10 A person stepping on the stepladder \vho needle to adjust the heigl1t ot the adjustable support foots for fitting a rugged ground can pull the steel slings 342 to balance the stepladder 2() Ho\vever. the axial actuator 34 of the present invention is not restricted to a plurality of screws 341 and a plurality of steel slings 342. It can be pull rods scre\v mounted onto the outer \all of the control ring 32. The pull rods extend out of the outer shell so that they can be pulled to control the elevation of the control r ino 32. The main purpose of the radial actuator 35 is to detach the retaining plates 2 form the screwed axle 11. Therefore. ens structure capable of achie\ ing the effect. such as a spring can be applied. not restricted to a screw 351. an elastic member 352 and a mo\ uble spacer 353 Further. the outer shell mav comprises onl! a rin', shell has in', a IT-shaped cross- section and a co\ er The outer shell can also be a part of the machine the adjustable support foot 's attached to. For example. the shaft 1 () I of the steplaclLler 1() can replace the ouster shell 4.

The present invention is thus described. and it a\ ill be oh\ ions that the sane ma! be varied in man\ ways. Such variations are not to be re'ardecl as a departure from the spirit and scope ol the JO present in\ ention. anti all such modifications as \\ould be oh\ ious to one skilled in the art are intended to be included \vithin the scope of the follo\\ing claims.

Claims

Claims i. An adjustable support foot comprising: a Support post having a

base with a screw axle mounted thereon, a plurality of retaining plates provided with screw threads on inner surfaces thereof and arranged to enclose and engage with the screw axle, and a control device comprising a retaining cylinder 1Q receiving said screw axle and retaining plates, and a control ring surrounding a portion of said retaining cylinder, said retaining cylinder having one or more apertures for receiving bearings for pressing against said retaining plates, the control device further comprising an actuator for moving said control ring between a first position in which urges said bearings against the receiving plates thereby causing the receiving plates to engage the screw axle and a second position in which the control ring does not urge said bearings against the retaining plates, thus allowing the retaining plates to disengage from the screw axle.
2 An adjustable support foot comprising,: a support post lea\ ant, a base and a scrc\\etl axle erectctl thereon: a pluralit! of retaining plates each pro\ ided \\ ith a scre\\ thread on an inner \vall thereof. a rim of an upper entl of each ol said retaining plates being pro\ idea with a tapered surface a rim of a lo\\er end of each of said retaining plates being provided with a transverse flange having a tapered surface: lO a control device including a retaining cylinder. a control ring.

a spring. an axial actuator and a radial actuator. said retaining cylinder being a hollow cylindrical body provided With a lo\ver receptacle hole and an upper axial hole. a top end of said receptacle hole being connected to said axial hole through a lo tapered section a \all of said retaining cylinder surrounding said receptacle hole being provided with a plurality oi in\\ardly tapered through holes each for housing a steel ball.

said control ring being a ring body enclosing said retaining cylinder, an inner \\;all having a plurality of slots, said spring coaxially situating in an upper portion of said retaining cylinder and constant!! pushing said control ring downward.

said axial actuator being connected to said control ring for controlling the elevation of said control ring. said radial actuator being connected to said retaining plates for pulling said retaining plates outward by an elastic means thereof; and an outer shell being a hollow shell body enclosing said control de\ice. said outer shell having two axial holes each on a top surface and a bottom surface thereof. said bottom axial hole further including an up\\arLll! tapered section: hereb! at least t\\o retaining plates are used to engage said scre\\et1 axle of said support post and then housed in said receptacle hole of said retainin c! tinder. said retainin' plates being secured \\ithin said retaining c! finder h! engaging, said upper tapered surfaces of said retainin plater \\ith said tapered section of said retaining cylinder and said 1() flanges of said retainin plates \vith said tapered section of said outer shell. said axial actuator and said radial actuator capable of being controlled from outside for quickl! adjusting the height of said adjustable support foot.
3 I he ad justable support foot of claim 2 \\,herein the shalt ol 1: said base of said support post is selected from the group ol a fixed shaft and a shrivel shaft.
4. I he adjustable support foot of claim 2 \herein said retaining plates are elongated plate having an arced trans,erse cross-section and each provided,vith a screw hole for connecting said radial actuator.
5. The adjustable support foot of claim 2 wherein the number of said retaining plates Is determined by the diameter of said scrc\ved axle of said support post.
6 The adjustable support foot of claim 2 wherein said retaining AS cylinder of said control device is of T-shaped lateral cross-section and is pros ided \ith a ring flange at an upper end thereof.
7 The adjustable support foot of claim 2 \herein said control rino of said control de\ ice is provided \\ith a pluralit! cat elongated slots for situating said axial actuator.
8. I he ad instable support foot of claim 2 \herein saitl axial actuator of said control device is a pluralit! of scre\s sect within the lateral \\all of said control ring. wherein each ol said screws is \wont1 around by a steel sling. and \herein each of said steel slings extentis out of said outer shell so that the! can be pulletl Irom outside.
9. The adjustable support foot of claim 2 \vherein saitl axial actuator of said control crevice is a pull rod screw-mounted can the outer lateral wall of said control ring. said pull rod extending out of the outer lateral \vall of said outer shell.
10. The adjustable support foot of claim 2 wherein said ratlial 1 actuator of said control device is a plurality of scre\vs 'on, through said outer shell. said control ring and said retaining cylinder anti connected to said retaining plates. each of said screws further including an elastic member and a spacer for urgin said retaining plates to move out\vard.

2O
11. The adjustable support foot of claim 2 wherein said outer shell further comprises a lateral wall, an upper cover and a lo\ver cover. \\herein said lateral \all is provided with screw threatis each around an upper rin1 and a louver rim thereof for securing, said upper cover and said lo\ver cover. \herein said lateral wall is further provided with a plurality of through holes for passing said radial actuator. wherein said upper cover is of U-shapetl lateral cross-section. and is provided v with a scre\v thread around an inner lateral wall thcrcot'and a plurality of through holes for passing, said steel slings and an axial hole on the top surface thereof. anti \vherein said lo\\er corer is of li-shapetl lateral cross-section and is pros ided \\ ith a scre\ thread around an inner lateral \all thereof and an axial hole anti an up\\ artil! laperetl conic hole on a bottom surl'act llereof.
12. 'I'he adjustable support t'oot as hereinbefore described \\ tl reference to the accompany ink dra\vings I to 5.