US1089864A - Extension-ladder. - Google Patents

Description

H. & S. M. PISARZ.

EXTENSION LADDER.

APPLICATION FILED AUG. 5, 1913.

Patented Mar. 10, 1914 2 SHEETS-SHEET l.

6M ATTORNEVS WITNESSES 'l; INVENTOR5 QMM% H PM? Q enrr SATES PATENT OFFTGE.

HENRY PISARZ AND STASH 1V1. PISARZ, OF LOS ANGELES, CALIFORNIA.

EXTENSION-LADDER.

resasea.

To all whom it may concern Be it known that we, HENRY PISARZ and S'rasii M P'ISARZ, 1, a subject of the Emperor of Austriadlungary, and, 2, a citizen of the United States of America, residing at Los Angeles, in the county of Los Angeles and State of California, have invented certain ne t and useful Improvements in EX- tension-Ladders, of which the following is a specification, reference being had therein to the accompanying drawing.

This invention relates to extension ladders, and more particularly to that type of ladder used by lire departments for scaling walls and reaching points about a building that could not under ordinary CllGlllIl' stances be reached except by an extremely long ladder.

The primary object of our invention is to provide a compact extension ladder consisting of a base section, lower and upper intermediate sections and a top section these four sections being arranged to collapse into a compact form, whereby the ladder :an be easily carried by a fire apparatus or vehicle.

A further object of this invention is to provide a strong and durable sectional extension ladder that has the sections thereof arranged whereby they can be easily and quickly extended to provide a safe structure that can be easily ascended or descended.

lVith the above and other objects in view the invention resides in the novel construction, combination and arrangement of parts to be hereinafter specifically described and then claimed.-

Reference will now be had to the drawiugs, wherein Figure 1 is a side elevation of the extension ladder collapsed, Fig. 2 is a rear elevation of the same, Fig. 3 is a vertical sec tional view of the extension ladder col lapsed, Fig. t is a cross sectional view of the same, Fig. 5 is a side elevation of a portion of the ladder extended, Fig. 6 is an enlarged detail sectional view of a portion of the ladder, Fig. 7 an enlarged longitudinal sectional view of the ladder extended and partly broken away, showing one side thereof, and Fig. 8 is a similar view showing the opposite side of the ladder.

A ladder in accordance with this invention embodies a base section, a lower intermediate section, an upper intermediate section, and a top section arranged to slide to- Specification of Letters Patent.

Application filed August 5, 1913.

Patented Mar. 10, 1914.

Serial No. 783,201.

gether, whereby the ladder when collapsed will have a longitudinal dimension corresponding to the length of one of said sections, especially the base section. All of the sections with the exception of the top section have hand rails whereby the ladder can be safely ascended or descended.

The base section comprises stiles 1 and 2 having the confronting sides thereof provided with angle bars 3 that are cut away, as at 1 to accommodate transverse rounds 5. The stiles 1 and 2 are provided with equally spaced arms (3 that are arranged at right angles to the front edges of said stiles, and said arms are connected together by longitudinal hand rails 7 that cooperate with the angle bars in forming guides for the lower intermediate section.

The rear edges of the stiles 1 and 2 are provided with bearings 8 for the spindle 9 of a revoluble roller or Windlass 10. The end of the spindle 9, at the stile 2 is provided with a detachable crank handle 11 and a ratchet wheel 12. The ratchet wheel 12 is engaged by a pivoted pawl. 13 carried by the stile 2 and said pawl is held in engagement therewith by a spring 1.4; arranged in a strap 15 carried by the stile 2. The pawl can be locked in or out of engagement with the ratchet wheel 12 by a pivoted dog 16 carried by the stile 2.

The stiles 1 and 2 have the confronting sides thereof, at the upper ends provided with bearing blocks 17 and connected to said bearing blocks are pulleys or sheaves 18. The bearing block 17 of the stile 1 has a stop 19 and the bearing block of the stile 2 has a catch 20, the object of which will presently appear.

The lower intermediate section comprises stiles 21 and 22 provided with angle bars 23, rounds 2+1, arms 25 and hand rails 26. The hand rails 26 and the angle bars 23 constitute guides for the upper intermediate section, and the stiles 21 and 22 of the lower intermediate section slide in the guides formed by the angle bars and the hand rails 7 of the base section. The confronting sides of the stiles 21 and 22, at the lower ends thereof, are provided with sheaves or pulleys 27 and the stile 21 has a stop pin 28 adapted to engage the stop 19 and limit the upward movement of the lower intermediate section.

The confronting sides of the stiles 21 and 22 at the upper ends thereof, are provided with bearing blocks 29 and 30, the bearing block 29 of the stile 21 being cut away, as shown in Fig. 3 to provide clearance for the stop 19. The bearing blocks support sheaves or pulleys 31 and the bearing block 30 is provided with a strap 32 and pivotally mounted upon the upper end of the stile 22 is a pivoted bell crank 33 that extends through the strap 32 and is engaged by a compression spring 34. ()ne end of the bell crank is in the path of the catch 20 and the opposite end thereof extends into the upper intermediate section.

The upper intermediate section comprises stiles 35 and 35 having angle bars 36, rounds 37, arms 38 and hand rails 39, said hand rails and said angle bars providing guides for the top section of the ladder. The stiles 35 and 35 slide in the guides formed by the hand rails 26 and the angle bars 23 of the stiles 21 and 22 and the lower confronting ends of the stiles and 35* have sheaves or pulleys 40. The lower end of the stile 35 has a combined cam and stop 41 that is engaged by the bell crank 33 to limit the upward movement of the upper intermediate section relatively to the lower intermediate section.

The upper confronting ends of the stiles 35 and 35 are provided with bearing blocks 42 and 43, said blocks supporting sheaves or pulleys 44. The block 43 is cut away and provided with a stop 45 that engages the bell crank 33 when the ladder is collapsed. The block also has a stop 46 that engages a pin 47, carried by the stile 48 of the top section, said top section having another stile 49, with said stiles connected together by rounds 50. The lower end of the stile 48 has another pin 51 that is engaged by the stop 46 whereby the top section will be limited in its upward movement. The top section slides in the guides formed by the hand rails 39 and the angle bars 36 of the stiles 35 and 35 of the upper intermediate section.

The lower ends of the stiles 48 and 49 oi the top section are provided with eyes 52 and extending through said eyes is a cable 53. The cable 53 passes over the sheaves 44, under the sheaves 40, over the sheaves 31, under the sheaves 27, and over the sheaves 18, said cable having the ends thereof attached to and wound upon the roller or Windlass 10. When the ladder is collapsed one end of the bell crank 33 extends under the stop 45 and the other end under the catch 20. As the Windlass is revolved, the top section is gradually elevated until the Gopies of this patent may be obtained. for five cents each, by addressing the Commissioner eyes 52 are in proximity to the sheaves 44 at which time the stop 51 engages the stop 46 and a further movement of the roller or windlass 10 causes the upper intermediate section to move, carrying with it the top section. The lower intermediate section is prevented from moving by the end of the crank 33 extending under the catch 20. As the upper intermediate'section'is elevated the combined catch and stop 41 engages the end of the crank 33 and the opposite end of the crank is forced out from under the catch 20, thereby freeing the lower intermediate section to permit of the same being elevated, and it can be elevated until the pin 28 en gages the stop 19 of the base section.

Assuming now that the ladder is to be collapsed, the pawl 13 is moved out of engagement with the ratchet wheel 12 and by hold.- ing onto the crank 11 it can be gradually collapsed without any danger of the sections thereof being injured. The lower intermediate section first rides into parallelism with the base section and as the lower intermediate section descends, the catch 20 knocks the end of the crank 33 out of engagement with the combined stop and cam 41 and the upper intermediate section can descend. Immediately upon the stop 45 of the upper intermediate section engaging the end of the crank 33, the top section descends into the guides of the upper intermediate section.

It is thought that the operation and utility of our extension ladder will be apparent without further description, and while in the drawings there is illustrated a preferred embodiment of the invention it is to be understood that the structural elements are susceptible to such variations and modifications as fall within the scope of the appended claim.

hat we claim is An extension ladder comprising a plurality of sections, each having a guide bar thereon and laterally projecting arms carrying hand rails parallel to the stiles of the section, and guide bars so arranged that the hand rails and guide bars of the lower section constitute embracing guides for the next upper section. V

In testimony whereof we aflix our signatures in the presence of two witnesses.

HENRY PISARZ. STASH M. PISARZ.

Witnesses Josnrrr GNozDonKI, JOSEPH SToMBRYs.

of Patents,

Washington, D. C.

Images