US2613830A - Lift truck fork - Google Patents

Lift truck fork Download PDF

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Publication number
US2613830A
US2613830A US14970A US1497048A US2613830A US 2613830 A US2613830 A US 2613830A US 14970 A US14970 A US 14970A US 1497048 A US1497048 A US 1497048A US 2613830 A US2613830 A US 2613830A
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Prior art keywords
rails
tracks
tractor
tines
rams
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US14970A
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Louie H Ponnequin
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66FHOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F9/00Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
    • B66F9/06Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks

Definitions

  • This invention relates to novel and useful improvements in lifting and transporting apparatus.
  • An object of this invention is to lift a bale or other package and transport the same by improved means.
  • Another object of this invention is to frictionally engage the sides of a bale or the like, lift the same and transport it.
  • Another object of this invention is to provide a pair of rails by means of a suitable pivot on the tractor or prime mover, supply a plurality of tracks transversely of the rails and in slidable engagement therewith and also provide Work engaging tines slidable in thesaid tracks.
  • Another object of this invention is to hydraulically actuate the said work engaging tools.
  • a still further purpose of this invention is to selectively control the actuation of the hydraulic actuation means.
  • Another object of this invention is to provide a generally improved lifting device for use in transporting bales, packages or other impedimenta'.
  • Figure 1 is an elevational side view of the preferred form of the'invention
  • FIG. 2 is a schematic diagram of the hydraulic system utilized in association with the invention and forming a portion thereof:
  • Figure 3 is a sectional view of the lift means illustrated in Figure 1;
  • Figure 4 is a transverse sectional view of the detail of construction shown in Figure. 3 and taken substantially on the line 4-4 thereof and in the direction of the arrows;
  • Figure 5 is a transverse sectional view' taken on the line 55 of Figure 3 .and in the direction of the arrows;.and I- 'i I Figure 6 is a longitudinal sectional view taken substantially one line 66 of Figure 3 and in the direction of the arrows.
  • a conventional tractor or prime mover is generally indicated at H] and provided with various and sundry appurtenances contiguous to and conventional to tractors or prime movers of this nature.
  • a pair of vertical rails having a channel-like cross-section are indicated at l2 and I4 respec- 2 Claims. (01. 214115) tively and are connected by means of a head rail or header [6 at one pair of ends thereof.
  • Fish plates I8 extend from the said rails l2 and I4 and have conventional pivot pins 20 interconnecting the rails with the chassis of the tractor It.
  • Means for pivotally actuating the rails l2 and I4 respectively may be provided if found desirable, this being a conventional fixture or apparatus.
  • sions of the channel-shaped rails and are slidable therein.
  • the tracks are attached directly to the shoes and are vertically slidable therewith.
  • Means for actuating the work engaging tines 32 and 34 respectively is provided.
  • the preferable means may be seen. best in Figure 3 wherein'a pair of hydraulic rams 36' and 38 respectively, including a'pair of cylinders 35 and 31' having v piston rods and 42 are illustrated as being attached to the tines 32 and 34 by means of small brackets 44 and 46 respectively. These small brackets are integrally associated with the said tines as by Welding, forming of a single cast,"
  • This means consists of a pair of plates 50 having pivot pins 52 associated therewith. Also secured to thesaid pivot pins is a telescopically adjustable shaft construction 'generally indicated at 54.
  • This shaft construction terminates in a conven-
  • the means for actuating the hydraulic rams I may be seen best in Figures 1 and 2 wherein there is disclosed a pump attached to the said tractor H) and an oil reservoir 62 suitably located on the tractor.
  • a filter 64 may be supplied in the supply tank 62 to serve its usual and. con- Theseshoes have an external configuration complemental to the internal dimen- 2a and 30.
  • ventional function and a line or conduit 66 connects the filter with the said pump 60.
  • Hydraulic fluid or the like is conducted through a flexible tube or conduit 68 over a sheave l0, thence to the inlet side of the hydraulic ram 38. Before extending over the sheave however,- the conduit 68 extends to a four-way selector valve 1!.
  • a pressure relief valve 14 Interposed in the conduit or line 68 is a pressure relief valve 14 which has a return line it extending to the tank 62.
  • a second conduit 18 flexible in nature interconnects the second selector valve 80 for use in association with the second ram 36.
  • Conduits 8i and 02 respectively extend from the selector valve 82 at both endsof theram 38 for application of fluid to either side of thepiston therein.
  • a conduit 89 extends from the selector valve H toone end of the said ram 38 while the said flexible, conduit 68 extends through the other end.
  • fluid may be directed to either side of the pistons in the said rams or may be bypassed from the selector valve H to the selector valve 80-when it is found desirable.
  • a return line 39 extends from the selector valve 80 to thetank 62 wherein the exhausted fluid is deposited for recirculation.
  • each selector valve H and 80 may be manipulated to the positions of providing fluid toeach end of the rams, to be bypassed from one selector Valve to the other or may be set to the entirely closed position.
  • Figure 6 discloses that a pair of shoes or runners I00 and I02 respectively are preferably rigidly secured to said work engaging tinesand are fitted within the confines of the tracks. This permits the desired sliding movement and obviates undesired transverse movementrelative to' the desired travel of the work engaging tines.
  • all of the rails22, 24 and 26 may be interconnected by means of connecting rods Hie which forman operative portion of the said shoes This expedient forms a carriage and is resorted to for smoothness in operation.
  • a tractor having a pump, a pair of vertical rails pivotally secured at their lower ends to said tractor, transverse tracks slidably secured in said rails, laterally movable work engaging tines slidably positioned in said transverse tracks, means for slidably actuatin said tracks in said rails, means for slidably actuating said tines toward and away from each other, and means for communicating said last mentioned means with the pump, said tine actuation means comprising rams having pistons slidable in a direction perpendicular to said rails, said communicating means comprising a plurality of flexible conduits, a shaft journalled between said rails, sheaves on said shaft having said conduits positioned thereon, valves in said conduits for controllin the flow from the pump and rams.
  • a lift and transporting apparatus comprising, a tractor having a pair of vertical rails pivotally attached at their lower ends thereto, transverse tracks extending between said rails, shoes vertically slidable in said rails and secured to said tracks, thereby mounting said tracks in said rails for vertical movement, means secured to one of said tracks and including an extensible shaft assembly for raising and lowering said tracks, work-engaging tines slidable in said tracks longitudinally of said tracks, hydraulically actuating means for moving said tines toward and away from each other, control valves secured to said tractor for regulating said hydraulically actuating means, said actuating means including a "pump on the tractor and rams, each ram includventional levers I 06 forsteering of the vehicle and I08 for regulating the speed of the vehicle or tractor I0 as well as the stand H2 for supporting an individual are supplied in association with the conventional tractor Hi to serve their usualfunction. All other necessary appurten'ancescontiguous to such types of tractor are supplied in association with the tractor in order to render the
  • each piston having means connecting it to one of said tines, a header connecting the upper endsof said rails, a shaft journaled between said rails and having sheaves thereon, and flexible conduits intercommunicating said rams and said pump and locating on said sheaves.

Description

Oct. 14, 1952 H. PONNEQUIN LIFT TRUCK FORK 2 SHEETS-SHEET 1 Filed March 15, 1948 Lou/e H. Ponnequin INVENTOR.
2 SHEETSSHEET 2 Oct. 14, 1952 Filed March 15, 1948 Lou/e H. Ponnequin INVENTOR.
BY M
Patented Oct. 14, 1952 LIFT TRUCK FORK Louie H. Ponnequin, Honolulu, Territory of Hawaii Application March 15, 1948, Serial No. 14,970
This invention relates to novel and useful improvements in lifting and transporting apparatus.
An object of this invention is to lift a bale or other package and transport the same by improved means. i
Another object of this invention is to frictionally engage the sides of a bale or the like, lift the same and transport it.
, Another object of this invention is to provide a pair of rails by means of a suitable pivot on the tractor or prime mover, supply a plurality of tracks transversely of the rails and in slidable engagement therewith and also provide Work engaging tines slidable in thesaid tracks.
Another object of this invention is to hydraulically actuate the said work engaging tools.
A still further purpose of this invention is to selectively control the actuation of the hydraulic actuation means. Y
. Another object of this invention is to provide a generally improved lifting device for use in transporting bales, packages or other impedimenta'.
Ancillary objects and features of novelty will become apparent to those skilled in the art, in following the description of the preferred form of the invention, illustrated in the accompanying drawings, wherein: I
Figure 1 is an elevational side view of the preferred form of the'invention;
Figure 2 is a schematic diagram of the hydraulic system utilized in association with the invention and forming a portion thereof:
Figure 3 is a sectional view of the lift means illustrated in Figure 1;
Figure 4 is a transverse sectional view of the detail of construction shown in Figure. 3 and taken substantially on the line 4-4 thereof and in the direction of the arrows;
Figure 5 is a transverse sectional view' taken on the line 55 of Figure 3 .and in the direction of the arrows;.and I- 'i I Figure 6 is a longitudinal sectional view taken substantially one line 66 of Figure 3 and in the direction of the arrows.
Referring now to the accompanying drawings, wherein like reference characters are .used throughout to indicate similar elements, there is illustrated a device or apparatus which is characteristic of the present inventive concept. A conventional tractor or prime mover is generally indicated at H] and provided with various and sundry appurtenances contiguous to and conventional to tractors or prime movers of this nature. A pair of vertical rails having a channel-like cross-section are indicated at l2 and I4 respec- 2 Claims. (01. 214115) tively and are connected by means of a head rail or header [6 at one pair of ends thereof. Fish plates I8 extend from the said rails l2 and I4 and have conventional pivot pins 20 interconnecting the rails with the chassis of the tractor It. Means for pivotally actuating the rails l2 and I4 respectively may be provided if found desirable, this being a conventional fixture or apparatus.
Referring now primarily to Figures 3-5,there is illustrated a plurality of tracks 22, 24. and 26 respectively. These tracks are slidably received in thesaid channel-shaped rails l2 and [4 respectively through the expedient of the shoes 28 and 30.
sions of the channel-shaped rails and are slidable therein. The tracks are attached directly to the shoes and are vertically slidable therewith.
Means for actuating the work engaging tines 32 and 34 respectively is provided. The preferable means may be seen. best in Figure 3 wherein'a pair of hydraulic rams 36' and 38 respectively, including a'pair of cylinders 35 and 31' having v piston rods and 42 are illustrated as being attached to the tines 32 and 34 by means of small brackets 44 and 46 respectively. These small brackets are integrally associated with the said tines as by Welding, forming of a single cast,"
brazing or the like. The opposite ends of the rams are secured to alternate shoes 28 and 30. thereby rendering. the rams slidable with the work engaging tines 32 and 34. Upon application of a force to the piston rods 40 and 42, the work engaging tines 32 and 34 will be actuated parallel to the tracks or transversely of the rails.
Means for raising and lowering the shoes and consequently the entire assemblage including the rams and work engaging tines is supplied. This means consists of a pair of plates 50 having pivot pins 52 associated therewith. Also secured to thesaid pivot pins is a telescopically adjustable shaft construction 'generally indicated at 54.
This shaft construction terminates in a conven- The means for actuating the hydraulic rams I may be seen best in Figures 1 and 2 wherein there is disclosed a pump attached to the said tractor H) and an oil reservoir 62 suitably located on the tractor. A filter 64 may be supplied in the supply tank 62 to serve its usual and. con- Theseshoes have an external configuration complemental to the internal dimen- 2a and 30.
ventional function and a line or conduit 66 connects the filter with the said pump 60.
Hydraulic fluid or the like is conducted through a flexible tube or conduit 68 over a sheave l0, thence to the inlet side of the hydraulic ram 38. Before extending over the sheave however,- the conduit 68 extends to a four-way selector valve 1!.
Interposed in the conduit or line 68 is a pressure relief valve 14 which has a return line it extending to the tank 62.
Following the diagram of Figure 2, it will be seen that fluid extends through the pipe or conduit 60 to the pump 60 from the said tank 62.
Then, it extends through a suitable conduit to the overflow valve 19 then to the selector valve 1| and to the hydraulic ram 38. A second conduit 18 flexible in nature interconnects the second selector valve 80 for use in association with the second ram 36. Conduits 8i and 02 respectively extend from the selector valve 82 at both endsof theram 38 for application of fluid to either side of thepiston therein.
A conduit 89 extends from the selector valve H toone end of the said ram 38 while the said flexible, conduit 68 extends through the other end. By manipulation of the four-way selector valves, fluid may be directed to either side of the pistons in the said rams or may be bypassed from the selector valve H to the selector valve 80-when it is found desirable. A return line 39 extends from the selector valve 80 to thetank 62 wherein the exhausted fluid is deposited for recirculation.
, Insumming up, each selector valve H and 80 may be manipulated to the positions of providing fluid toeach end of the rams, to be bypassed from one selector Valve to the other or may be set to the entirely closed position.
Itwill be noted from an inspection of Figure 2 that. four flexible conductors are requisite for the'desired manipulation and actuation of the work engaging tines 32 and 34 and therefore, four-sheaveslu ar supplied on a common shaft 92.- ,This, common shaft extends between the railsflZ and Ill, wherein it is journalled.
In journalling the'said work engaging tines 32 and 34, inspection of Figure 6 discloses that a pair of shoes or runners I00 and I02 respectively are preferably rigidly secured to said work engaging tinesand are fitted within the confines of the tracks. This permits the desired sliding movement and obviates undesired transverse movementrelative to' the desired travel of the work engaging tines.
Further, all of the rails22, 24 and 26 may be interconnected by means of connecting rods Hie which forman operative portion of the said shoes This expedient forms a carriage and is resorted to for smoothness in operation. Con
While there has been described and illustrated but a preferred form of the invention, it is apparent that variations may be made without departing from the spirit thereof. Accordingly,
limitation is sought only in accordance with the scope of the following claims.
Having described the invention what is claimed as new is:
1. In a lifting and transporting apparatus, a tractor having a pump, a pair of vertical rails pivotally secured at their lower ends to said tractor, transverse tracks slidably secured in said rails, laterally movable work engaging tines slidably positioned in said transverse tracks, means for slidably actuatin said tracks in said rails, means for slidably actuating said tines toward and away from each other, and means for communicating said last mentioned means with the pump, said tine actuation means comprising rams having pistons slidable in a direction perpendicular to said rails, said communicating means comprising a plurality of flexible conduits, a shaft journalled between said rails, sheaves on said shaft having said conduits positioned thereon, valves in said conduits for controllin the flow from the pump and rams. I
2. A lift and transporting apparatus comprising, a tractor having a pair of vertical rails pivotally attached at their lower ends thereto, transverse tracks extending between said rails, shoes vertically slidable in said rails and secured to said tracks, thereby mounting said tracks in said rails for vertical movement, means secured to one of said tracks and including an extensible shaft assembly for raising and lowering said tracks, work-engaging tines slidable in said tracks longitudinally of said tracks, hydraulically actuating means for moving said tines toward and away from each other, control valves secured to said tractor for regulating said hydraulically actuating means, said actuating means including a "pump on the tractor and rams, each ram includventional levers I 06 forsteering of the vehicle and I08 for regulating the speed of the vehicle or tractor I0 as well as the stand H2 for supporting an individual are supplied in association with the conventional tractor Hi to serve their usualfunction. All other necessary appurten'ancescontiguous to such types of tractor are supplied in association with the tractor in order to render the same operative.
ing a cylinder with a piston therein, each piston having means connecting it to one of said tines, a header connecting the upper endsof said rails, a shaft journaled between said rails and having sheaves thereon, and flexible conduits intercommunicating said rams and said pump and locating on said sheaves.
LOUIE H. PONNEQUIN.
REFERENCES CITED The following references are of record in the file of this patent:
I UNITED STATES PATENTS Number
US14970A 1948-03-15 1948-03-15 Lift truck fork Expired - Lifetime US2613830A (en)

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Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2676723A (en) * 1951-10-22 1954-04-27 Yale & Towne Mfg Co Ram construction for industrial lift trucks
US2706570A (en) * 1952-12-12 1955-04-19 Vernon E Jewell Bale loading attachment for automotive vehicle
US2709016A (en) * 1952-08-07 1955-05-24 Baker Raulang Co Load gripper and carrier for an industrial lift truck
US2746630A (en) * 1952-10-16 1956-05-22 Anderson Clayton & Co Clamp for industrial trucks
US2748966A (en) * 1953-08-03 1956-06-05 Gerlinger Carrier Co Laterally adjustable tines for a lift truck
US2752054A (en) * 1953-02-02 1956-06-26 Irving C Thompson Industrial truck
US2775359A (en) * 1955-07-22 1956-12-25 Russell J Carpenter Paper roll handling attachment for industrial elevating trucks
US2788148A (en) * 1953-08-07 1957-04-09 Baker Raulang Co Load carrying industrial truck
US2800236A (en) * 1953-06-30 1957-07-23 Baker Raulang Co Self-unloading industrial truck
US3342361A (en) * 1964-10-05 1967-09-19 Thomas N Melin Pivotal fork assembly for fork-lift trucks
WO1981002001A1 (en) * 1980-01-07 1981-07-23 Towmotor Corp Side shift fork adjustable carriage
US4335992A (en) * 1980-01-07 1982-06-22 Towmotor Corporation Side shift fork adjustable carriage
US10531169B2 (en) 2015-09-11 2020-01-07 Ssv Works, Inc. Combination glove box and speaker box device
DE102009056479C5 (en) 2009-04-16 2023-01-19 Durwen Maschinenbau Gmbh Attachment for forklift trucks with adjustable load-bearing devices

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1518561A (en) * 1923-05-31 1924-12-09 Alexander W Carroll Lifting platform
US2178369A (en) * 1938-03-12 1939-10-31 Clark Equipment Co Industrial truck
US2292605A (en) * 1940-08-03 1942-08-11 Fruit Growers Exchange Ca Hand truck
US2420828A (en) * 1945-09-17 1947-05-20 Walter J King Stacking machine
US2432411A (en) * 1946-05-06 1947-12-09 Towmotor Corp Industrial truck
US2451943A (en) * 1946-05-20 1948-10-19 Clark Equipment Co Industrial truck
US2457366A (en) * 1946-08-29 1948-12-28 Towmotor Corp Industrial truck
US2475367A (en) * 1947-05-28 1949-07-05 Fred J Avery Clamp for lift trucks
US2509023A (en) * 1947-07-05 1950-05-23 Theodore F Vogel Jr Apparatus for handling unit loads
US2513928A (en) * 1947-12-03 1950-07-04 Towmotor Corp Hose support for lift trucks

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1518561A (en) * 1923-05-31 1924-12-09 Alexander W Carroll Lifting platform
US2178369A (en) * 1938-03-12 1939-10-31 Clark Equipment Co Industrial truck
US2292605A (en) * 1940-08-03 1942-08-11 Fruit Growers Exchange Ca Hand truck
US2420828A (en) * 1945-09-17 1947-05-20 Walter J King Stacking machine
US2432411A (en) * 1946-05-06 1947-12-09 Towmotor Corp Industrial truck
US2451943A (en) * 1946-05-20 1948-10-19 Clark Equipment Co Industrial truck
US2457366A (en) * 1946-08-29 1948-12-28 Towmotor Corp Industrial truck
US2475367A (en) * 1947-05-28 1949-07-05 Fred J Avery Clamp for lift trucks
US2509023A (en) * 1947-07-05 1950-05-23 Theodore F Vogel Jr Apparatus for handling unit loads
US2513928A (en) * 1947-12-03 1950-07-04 Towmotor Corp Hose support for lift trucks

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2676723A (en) * 1951-10-22 1954-04-27 Yale & Towne Mfg Co Ram construction for industrial lift trucks
US2709016A (en) * 1952-08-07 1955-05-24 Baker Raulang Co Load gripper and carrier for an industrial lift truck
US2746630A (en) * 1952-10-16 1956-05-22 Anderson Clayton & Co Clamp for industrial trucks
US2706570A (en) * 1952-12-12 1955-04-19 Vernon E Jewell Bale loading attachment for automotive vehicle
US2752054A (en) * 1953-02-02 1956-06-26 Irving C Thompson Industrial truck
US2800236A (en) * 1953-06-30 1957-07-23 Baker Raulang Co Self-unloading industrial truck
US2748966A (en) * 1953-08-03 1956-06-05 Gerlinger Carrier Co Laterally adjustable tines for a lift truck
US2788148A (en) * 1953-08-07 1957-04-09 Baker Raulang Co Load carrying industrial truck
US2775359A (en) * 1955-07-22 1956-12-25 Russell J Carpenter Paper roll handling attachment for industrial elevating trucks
US3342361A (en) * 1964-10-05 1967-09-19 Thomas N Melin Pivotal fork assembly for fork-lift trucks
WO1981002001A1 (en) * 1980-01-07 1981-07-23 Towmotor Corp Side shift fork adjustable carriage
US4335992A (en) * 1980-01-07 1982-06-22 Towmotor Corporation Side shift fork adjustable carriage
DE102009056479C5 (en) 2009-04-16 2023-01-19 Durwen Maschinenbau Gmbh Attachment for forklift trucks with adjustable load-bearing devices
US10531169B2 (en) 2015-09-11 2020-01-07 Ssv Works, Inc. Combination glove box and speaker box device

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