US1394498A - Ladder-raising device - Google Patents

Description

H. J. HOPKINS.

LADDER RAISING DEVICE.

APPLICATIVON man FEB. 18,1920.

Patented Oct. 18, 1921.

3 SHEETSSHEET l.

3 Int 1927601. a :52" .9 wm W a 8y /7 6. 45 8 flfl'aknt'y H. J. HOPKINS.

LADDER RAISING DEVICE.

APPLICATION FILED FEB. 18, 1920.

Patented 0013. 18, 1921.

s SHEETS-SHEET 2.

3O v a telescopic connection between the carriage vertical positionbefore it is ratchet PATENT OFFICE.

HUBER! J. HOPKINS, OF SAN FRANCISCO, CALIFORNIA.

LADDER-RAISING DEVICE.

Specification 01 Letters Patent.

Patented Oct. 18, 1921.

Application filed February 18, 1920. Serial No. 359,604.

T 0 all whom it may concern:

Be it known that 1, Hunter J. Horxrns, a citizen of the United States, residing at the city and county of San Francisco and State of California, have invented a new and useful Improvement in Ladder-Raising Devices, of which the following is a specificat-ion.

This invention relates to extension ladders such as employed by fire departments and the like and especially to a raising device to be employed in conjunction with the same.

One of the objects of the present invention is to provide a simple substantial rigid ladder of the extension type such as employed by fire departments and the like and especially to provide means for facilitating the extension and raising of the same. 9

Another object of the invention is to provide a carriage which is pivotally attached to the lower end of the ladder, said carriage serving two main functions; first that of temporarily supporting the ladder when re moved from the truck carrying the same,

and second that of a support about which the ladder may be swung to an approximate raised into position against a building or the like.

Another object of the invention is to form and the ladder which is operable independent of thepivotal connection and which automatically renders the carriage inoperable when the ladder assumes a vertical position. i

Another object of the invention is to provide a collapsible truss whereby the main ladderand the extension are rigidly braced when in an extended position.

Further objects will hereinafter appear. The invention consists of the parts and the construction, combination and arrange ment of parts as hereinafter more fully described and claimed, having reference to the accompanying drawings, in which- Figure 1 is a sideelevation of the ladder showing it extended and in position for use.

Fig. 2 is across section on line 2-2 of Fig. 3.

Fig. 8 is a side elevation of the section taken on line 3-3 of Fig. 2.

Fig. l is a detail view of the foot brace lock.

Figs. and 6 are detail views of the extended and 5 wheels and p'awls used eonjunca Fig. 11 is a detail view of the ladder sup-.

porting standards.

Fig. 12 is a detail view of the lateral braces employed in conjunction with the standards shown in Fig. 11.

Fig. 13 is a detail view in side elevation showing the ladder assuming a vertical position.

Fig. 14: is an enlarged detail sectional view of thetelescope mechanism employed in conjunction with the standards in Figs. 9 and 11.

Fig. 15' is a detail view of the securing means employed in connection with the standards shown in Fig. 11.

Fig. 16 is a plan view in section of the lifting pole lock taken on line 16-16 of Fig. 20. i

Fig. 17 is a side elevation of the keeper for supporting one end of the lifting pole when ont in use.

Fig. 18 is a cross section on line 18-18 of Fig. 17.

Fig. 19 is a cross section on line 19 19 of Fig. 20.

Fig. 20 is a side elevation of 16.

Fig. 21 is a detail view showing the locking up wedgesemployed to move a ladder across a sidewalk curb or other obstruction.

Referring to the drawingsin detail, A indicates the main or lower end of a ladder and 2 an extensible section which may be telescoped or extended with relation to the main section A. The ladder here shown is particularly adapted for lire service and the like, andone of the main features of the present invention is to provide means, for facilitating the raising and extending of the ladder, and further to provide means for rigidly bracing the extensible section with relation to the main section when the be supported at one end by means of a carriage B. This carriage is pivotally attached to the ladder'as at 3,, and it serves two main functions, first that of. supporting one end of the ladder when it assumes a horizontal position, such as shown in Fig. 9, and secondly that of'a' support about which the ladder may be swung into an approximate vertical position as indicated by dotted lines in Fig. 9 and by full lines in Fig. 1.

. The carriage proper consistsof frame sectionst and.5:, which are. rigidly connected by cross braces 6 and ashaft 7. Journaled on the shaft and. adapted to support the carriage. are a pair ofwheels. 8, and slidably mountedin. guide plates 9,- secured on each frame section. 4, are auxiliary bracing and locking legs, 10. These. legs assume the full line position. shown in Fig. 9 when the carriage is employed, but are otherwise raised into the dotted line position'indicated at 10. Each guide for the legs 10 consistsof a pair of interspaced plates9, between which the legs are slidably mounted. The upper ends of the legs are offset as at 11, and the frame sections 4: and 5 are notched asat 12 to receive the offset sections of the legs and to secure the same against upward movement when in anextendedposition. The legs 10 when lowered. are otherwise connected by a.

detachable chain 12 to prevent spreading of the-same and they are secured: in the raised positionindicatd by the dotted lines at 10 bv means of pins 13, whichpass through perforations l l fcrmedin the plate 15, and the upper ends ofthe legs proper as at 14*. The carriage may be'locked in vertical position, first by extending the legs-10, and secondly by means of an endless cable and chain 16. The cable section 16 passes over a pulley 17, while the chain section 18 passes over a sprocket wheel 19. The sprocket wheel. is journaled at the lowermost end of the ladder and is provided with aratchet wheel and pawl such as shown at 20 and 20respectively, to lock thechain and cable against movement consequently the carriage with the ladder assumes a horizontal position. This position is assumed immediately after the ladder is removed from the truck carry ing the same and the sprocket wheel19 is only releasedto permit the laddertobe freely turnedwhenthe pawl 20' is disconnected from the ratchet wheel 20 or when it is desired to tip' the ladder. about'the car= 'riageand swing into the dotted line position shown in F 9. This is of course only done when the ladder is in an approximate position with relation to the building or other object against which it is going to be raiser.

There are two pair of legs. 10; one pair for each frame section 4 and 5. There ar similarly twochain and. cable sections 18 and 16 and two sprocket wheels19 with respective cooperating pawls 20 and ratchets 20, thatis one set is arranged on each side of the ladder to positively secure the carriage B in vertical position when supporting the ladder and when raising the same. The only time that the pawl 20 is released is when the ladder is tilted. or swung about the pivotal connection '3; r

To materially facilitate the raising of the ladder or swinging of the same about the pivotal connection 3, I provide a foot. brace frame 21' and an auxiliary foot. brace 22i The frame 21' is pivotally. attached to the lower end. of. the ladder as at 23 and it. is held in an extended position by means of a pair of linksi2t, one-being pivotally connected to each side thereof. These links are furthermore pivotally attached. at their upperends to sliding blocks 25 whichstraddle. the-guide rods 26 and it is therefore possible to fold the foot brace 21. over against the ladder as shown inFig. 1, whenever desired, and similarly the auxiliary footbrace 22 as this is pivotally attached to the frame 21 and is connectedthereto by means of a chain 27, the frames 2land 22 being provided with rungs such as shown at 28 in Fig. 10, which register with or mayentirely displace rungs on the lower. end of the ladder. The. foot braces or. frames21 and 22 are employed when the ladder is tilted aboutthe pivotal the number of men required when raising or lowering the ladder. The foot bracesare. of course folded up against the ladderwhen it israised, and they are, thereforeonly useful during the; raising operation;

W1ththe ladder tlltGCl'OI swung. in the position shown in Fig. 1, 'lil' isposslble to temporarily support it by means. of pair.

of poles 29. said poles being also employed when raising the ladder into its final vertical position The poles are universally con nected with the lower sect-ionof the ladder so that the fireman may assume any-convenient position when. employing the same.

The universal connect-ion employed is shown in Figs. 1, 16,19 and20. The connection consists of a bracket'30, which is pivotally attached. to the ladder by means of a bolt 31. T ie bracket 30 supports a second bracket; 32. which is pivotally attached to the, bracket 30, by means of abolt 33 and as the bolts 31 and 33 are mounted at right angles to each other, it can readily be seen that if the pole is attached thereto, universal movement ofthe same will bepermitted. The bracket 32 carries a pair. of sheave-like rollers 34, between which the pole 29 passes. A pair of collars 35, secured on one endof the: pole however engage with the sheaves '34, whenthe. poleis extended, and thereby prevent the pole from passing between the same. If the pole is pulled along the ladder until the collars 35 engage the sheaves, it happens that the pole becomes locked against endwise movement with relation to the sheaves and the brackets and 32. This is accomplished by means of a latch 36 which is pivotally mounted in the pole as at 37 and projected automatically by means of a spring 38 when the poles extended posi tion is assumed, that is, latch 36 engages one side of the bracket 32 and thus locks the pole against endwise movement in one direction, while engagement oi the collars with the sheaves locks the pole against endwise movement in the opposite direction. The universal connection of the brackets 30 and 82, however permits universal movement of the free end of the pole. The ladder is also provided with a pair of fork-shaped brackets 39.. These are placed at the lower end of the ladder and are provided for the reception of the collars 35. This position of the pole in parallelism with the main section of the ladder, as shown by dotted lines in Fig. 1,. is only assumed when the poles are not in use, and this position can only be assumed when the latch 36 is released and the pole is pushed upwardly through the sheaves 34 to such an extent that when swung into parallelism with the ladder, the collars 35 will be received by the iorlrshaped bracket 39. There are two poles such as shown, one on each side oi: the ladder. Both are similarly constructed and a description 01" one should therefore suiiice.

Another important feature of the invention is the provision of means for raising the extension section of the ladder when the main ladder has been tilted into the position shown in Fig. 1. The extension ladder 1s telescopic with relation to the main ladder, it being slidably supported between the main side sections of ladder A as shown in Fig. 2. Raising of the extension is accomplished by means of a pair of pulleys 43 and hand cranks 421.1 The extension ladder may be locked in any raised position desired by securing the pulleys &3 against rotation by means of pawls and ratchet wheels as at It is however desirable to raise the extension ladder to its outermost limits as it is here possible to throughly brace the same and thereby materially increase the total strength of the ladder, as will hereinafter be described' The pulleys 13 each carry a. cable consisting of a chain section 4C5 and a rope section 45. One end of each cable is attached to the extension ladder at a point indicated at ti. The cables, referring to Fig. 1, terminate in chains 45 and pass over the pulleys 45. They then pass up between the rungs oi the respective ladder sections and under guide pulleys 46. (See Fig. 8.) They then pass over guide pulleys a? and are attached to the upper end of a pair of truss arms 48 which are pivotally secured to the lower end of the extension ladder 2, as shown at 49. Turning movement trans mitted to the pulleys 4-3 causes a pull on the chains and cable which are attached to the truss arms 48. Chains 48 restrain the truss arms 48 against further movement than the right angle position shown. The ladder section 2 is in this manner extended and will finally assume the completely extended po sition shown in Fig. 1. The cable and the chain 4C5 here assumes a taut position and as one end is secured at point 41% and the other end to the truss arms 48, it can readily be seen that the truss arms will be swung about their pivotal connections into the right angle position shown in Figs. 1, 2 and 8, thereby further increasing the tautness of the cable and chain 415, and to that extent forming a truss which materially increases the total strength of the ladder 2 extended, the important feature of this portion of the structure being the iact that the truss is collapsible and extensible and only assumes a taut and operable position when complete extension of the ladder is accomplished, the cables and the ladder section raised thereby being securely locked against release by the pawls and ratchets 42.

l Vith the ladder raised and extended as shown in Fig. 1, it is possible to employ the poles 29 and thereby raise the ladder to an approximate vertical position against the building or object where the ladder is'to be employed. of the ladder beyond the angular position shown in Fig. 1, automatically renders the supporting truck or carriage B inoperative. This is accomplished automatically, due to the fact that a telescopic connection is formed between the ladder and the frame sections 4: and 5 of the carriage. This telescopic connection is clearly shown in Figs. 13 and 1a. The pivotal connection between the ladder and the carriage is shown at 3, one section of each pivotal connection 3 carries a rod 50, which passes through a guide member 51 in the upper end of the carriage frame. As the ladder is being swung beyond the angular position shown in Fig. 1 by means of the poles 29, it can be seen that the telescopic connection formed will automatically extend itself as shown in Fig. 13, and that the carriage gradually swings up against the ladder where it maybe locked by means of the hooks 52, shown in Fig. 1. It thus becomes inoperable as it is impossible for the cariage to support any weight when the telescopic connection is extended and any danger oi the lower end of the ladder slipping or giving is therefore obviated.

lit it is desired to lower the ladder, it is first necessary to swing it into an angular position where the telescopic connection of the carriage reaches its innermost limit and Where the pivotal connection 3 can begin to take the weight of the ladder. The ladder is then supported by means of the poles 29, while the pawls and ratchets at 4-2 are released. The hand cranks 41 are then employed and turned in a direction which permits the ladder sections 2 to return to normal position. The truss arms 48 automatically swing upward into parallelism with the ladder when this takes place and a flat surface will therefore be presented as no projections are desirable. The foot brace frames 21 and 22 are next extended and the ladder swung into the horizontal position shown in Fig. 9.

The poles are released by means of V the latches 36 and these are run back between the sheaves 34C to a position where the collars S5 engage the fork-shaped brackets 89. The pawls 20 are then brought into engagement with their respective ratchets 20 and the cables and chains 16 and 18 will thus secure the carriage B in vertical position. The chains 12 may then be disconnected andthe auxiliarybracing legs raised to the dotted line position shown at 10 The ladder may then be rolled over to the truck provided for its reception and maybe temporarily supported at its outer ends by a pair of extension legs 60. (See Fig. 1.) The pawls 20 are again released and the carriage B swung up into parallelism with the ladder as shown by dotted lines in Fig. 9, it being here secured by the hooks 52. The foot braces are of course folded into parallelism with the ladder and the temporary supporting legs 60, similarly folded. The ladder is then grasped by the men and slid endwise on the truck Where it may be secured in any suitable manner. Tn removing the ladder it is pulled off endwise and the legs 60 extended to support the outer end. T he carriage is then released and swung into vertical position and is locked in this position by swinging the pawl 20 into engagement with its cotiperat ing ratchet'gear. The ladder may then be 7 rolled along the ground as it'is supported by the carriage to a point where 1t is to be used. and if obstructions of any kind are encoun-f tered, such as a gutter or the like, wedge shape l lock, surh as shown in Fig. 21, may be employed to permit the carriage to over the obstruction. When the ladder has reached itsposition, it is only necessary :to disengage thepawl 20 and to extend the foot braces 21 and 22. These are then grasped by the men and sullicient weightapplied to tilt the ladder into the position shown in Fig. 9. The upper sect on of the ladder is then eXte-ndedas previously described and the ladder is finally raised to a vertical position by the poles 29, the carriage of course becoming inoperable when a vertical position is assumed, due to the telescopic action of the connections 50 and 51.

By referring to Fig. 9 it will be seen that the cable 16 is provided with a stop member 16. This stop member engages the pulley 17 when the ladder assumes a horizontal position, and it therefore locks the upper or forward end of the ladder from tilting, while the pawl and ratchet on the opposite pulley 19 looks it against tilting in the direction indicated by the dotted lines.

Having thus described my invention, what l claim and desire to secure by Letters Patent is.

1. The combination with a ladder of the character described, of a carriage adapted to support one end thereof, wheels on the carriage, means permitting tilting movement of the ladder with relation to the carriage, means forloclring the ladder against tilting movement about the carriage, and means permitting vertical movement j of the carrings with relation to the ladder.

The combination with a ladder of the character described, of a carriage adapted to support one end thereof, wheels on the carriage, means permitting tilting movement of the ladder with relation to the carriage, m ans for locking the ladder against tilting movement about the carriage, means permiting vertical movement of the carriage with relation to the ladder, and means for 00- operating with the wheels on the carriage for locking the carriage against rolling movement. i

8. The combination with a ladder of the character described, of a carriage adapted to support one end thereof, a pivotal connection between the carriage and the ladpermitting tilting movement of the ladder, means for locking the ladder k inst tilting movement when the carriage assumes a vertical position and the ladder a horizontal position, wheels supporting the carriage, and means rooperating with the wheels for locking the same against rollmovement, said means comprising a pair of auxiliary bracing members for each wheel, said bra-sing membersadaptedtobe secured to thecarriageat their upper ends and to engage the ground at their lower ends. I Y a l. The combination with a ladder of the 'character described, of a carriage adapted to riageat their upper ends and to engage the,

ground at their lower ends, and means permitting vertical movement of said members to raise the same out of engagement with the ground, and means for securing the same in vertical position on the carriage.

5. The combination with a ladder of the character described, of a carriage adapted to support one end of the ladder, a pivotal connection between the ladder and the carriage, a telescopic connection permitting vertical movement of the carriage with relation to the ladder, wheels on the carriage, means for securing the carriage against movement on the wheels and means for locking the ladder against tilting movement about its pivotal connection.

6. The combination with a ladder out the character described, of a carriage adapted to support one end of the ladder, a pivotal connection between the ladder and the carriage, a telescopic connection permitting vertical movement of the carriage with relation to the ladder, wheels on the carriage, means for securing the carriage against movement on the wheels, means for locking the ladder against tilting movement about its pivotal connection, said means comprising an endless cable secured to the lower end of the carriage, a chain section in said endless cable, a sprocket over which said chain passes, and means for securing the sprocket against turning movement.

7. The combination with a ladder of the character described consisting of upper and lower telescoping sections, of a support for one end thereof by which the ladder is adapted to be tilted, the lower section of the ladder and support being of such lengths when the ladder is swung beyond the predetermined vertical angular position the support becomes inoperable.

8. The combination with a ladder of the character described consisting of upper and lower telescoping sections, of a carriage adapted to support one end thereof, and a pivotal connection between the support and the ladder permitting tilting movement of the ladder about the support, the lower sec tion of the ladder and carriage being of such lengths that when the ladder is swung beyond a predetermined vertical position, the carriage support is rendered inoperable.

9. The combination with a ladder of the character described consisting of upper and lower telescoping sections, of a carriage adapted to support one end thereof, a pivotal connection between the carriage and the ladder permitting tilting movement of the ladder about the carriage, the lower section of the ladder and carriage being of such lengths that when the ladder is swung beyond a predetermined vertical position, the carriage support. is rendered inoperable, and a pair of foot braces secured to the lower end of the ladder and foldable with relation thereto whereby the ladder may be grasped for tilting.

10. The combination with a ladder oi the character described, consisting of upper and lower telescoping sections, or a carriage adapted to support one end thereof, a pivotal connection between the carriage and the ladder permitting tilting movement of the ladder about the carriage, a telescoping connection between the pivot and the carriage, the lower section of the ladder being of such length that when the ladder is swung beyond a predetermined vertical position, the teles oping connection between the pivot and the carriage will become extended and render the carriage inoperative, a pair of foot braces secured at the lower end of the lad der and toldable with relation thereto, whereby the ladder may be grasped when it is tilted, and means for locking said foot bra es when folded against the ladder.

11. The combination with a ladder of the character described, of an extensible section on the ladder adapted to be raised or lowered with relation thereto, a collapsible truss connecting the extensible section with the main section of the ladder, and means for causing said collapsible truss to assume a taut position when the extensible section is completely extended.

12. A ladder comprising a lower main section. and an upper extensible section, a cable attached to one end of the approximate upper end or the extensible section, a truss arm pivetally mounted on the lower end of the extensible section, a guide on one end of said truss arm over which the cable passes, a sprocket wheel on the lower end of the main section of the ladder over which the cable passes, means "for securing the end of the cable to one end of the truss arm, and means for exerting a pull on the cable to raise or lower the extensible section.

13. A ladder comprising a main lower section and an extensible upper section, a sprocket gear journaled in the lower end of the main ladder, a truss arm pivotally mounted on the lower end of the extensible section, a cable attached to one end of said truss arm, said cable passing downwardly from the truss arm around the sprocket and then upwardly past the free end of the truss arm, means securing this end of the cable to a point near the upper end of the extensible ladder section, a chain section in the cable passing over the sprocket, and means for imparting a rotary movement to the sprocket in either direction to raise or lower the eX- tensible ladder section.

14:. A ladder comprising a main lower section and an extensible upper section, a sprocket gear journaled in the lower end of the main ladder, a truss arm pivotally mounted on the lower end of the extensible section, a cable attached to one end of said truss arm, said cable passing downwardly from the truss arm around the sprocket and then upwardly past the free end of the truss arm, means securing this end ofthecable to a point near the upper end of the extensible ladder section, a chain section in the cable passing over the sprocket, means for imparting a rotary movement to the sprocket in either direction to raise or lower the extensible ladder section, means on the free end of the pivotally mounted truss arm for engaging and guiding the cable, and means for limiting the swinging movement or" the truss arm.

15. The combination with a ladder, of a raising pole therefor, a bracket at the upper end of the ladder through which the pole extends, a universal connection between said bracket and the ladder, means permitting.

enowise movement of the pole through the bracket, and means on one end of the pole for lockingv the pole'against endwise movement with relation to the bracket.

16. The combination with a ladder, of a raising pole therefor, a bracket at the upper end of the ladder through which the pole extends, a universal connection between said bracket and the ladder, means permitting endwise movement of the pole through the bracket, and means on one end of the pole for locking the pole against endwise movement with relation to the bracket, said means comprising a latch engageable with one side of the bracket and a collar on the pole engageable with the other side of the bracket.

In testimony whereof I have hereuntoset my hand in the presence of two subscribing witnesses.

HUBER-T J. HOPKINS. VJitnesses W. V7. HEALEY, M. E. EWING.

Images