Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.


  1. Advanced Patent Search
Publication numberUS968312 A
Publication typeGrant
Publication dateAug 23, 1910
Filing dateMay 10, 1909
Priority dateMay 10, 1909
Publication numberUS 968312 A, US 968312A, US-A-968312, US968312 A, US968312A
InventorsGeorge Dudley Bacon
Original AssigneeGeorge Dudley Bacon
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 968312 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

l G. D. BACON.



968,312. Patented Aug. 23, 1910.

v 5 V 2019 1 29.2 2 2 21 Z3 5 i5 Gear zflliawnr a tn 2: I Q: 4 y l GEORGE DUDLEY BACON, OF GUERNEVILLE, CALIFORNIA.


Specification of Letters Patent.

Application filed May 10, 1909.

Patented Aug. 23, 1910. Serial No. 495,046.

To all whom it may concern:

Be it known that I, GEORGE DUDLEY BA- ooN, a citizen of the United States, residing at Guerneville, in the county of Sonoma and State of California, have invented a new and useful Logging-Jack, of which the following is a specification.

This invention relates to a jack especially adapted for lifting logs and other heavy objects, and the invention relates more particularly to the provision of a jack of that type consisting of opposed racks operated through a crank-driven pinion.

The invention has for its principal object to provide a jack of this character which. is of durable and substantial construction, capable of exerting a great power, and which is readily manipulated.

Another object of the invention is the provision of relatively-movable rack bars on which is mounted a carriage or frame carrying a pinion for moving the rack bars, together with the operating mechanism for the pinion, there being anti-friction devices between the relatively-movable parts to insure easy working.

Vith these objects in view and others, as will appear as the description proceeds, the invention comprises the Various novel features of construction and arrangement of parts which will be more fully described hereinafter and set forth with particularity in the claims appended hereto.

In the accompanying drawing, which illustrates one embodiment of the invention, Figure 1 is a side View of the jack. Fig. 2 is a horizontal section on line 22, Fig. 1. Fig. 3 is a section on line 33, Fig. 2. Fig. 4 is a section on line 4-4, Fig. 2. Fig. 5 is a vertical section on line 55, Fig. 1. Fig. 6 is a horizontal section on line 6-6, Fig. 1. Fig. 7 is a top plan view of the upper portion of the jack.

Similar reference characters are employed to designate corresponding parts throughout the views.

Referring to the drawing, 1 designates the standard of the jack, which has its lower end set into a socket 2 of a base piece or foot 3 that extends laterally from the standard and is provided with projections 4 to grip in the surface on which the jack is supported, so as to prevent slipping, the footpiece providing a broad and stable base for the jack. Disposed arallel with the standard is a vertical li ting element 5 in the form of a bar which carries at its lower end a guide 6 engaging the standard 1 and which, at its upper end, passes-through a guide 7 fixed on the standard. As shown in F ig 6, the guide 6 is a rectangular member having a socket or opening 8 in which the lower end of the lifting element 5 is rigidly secured, and at one side of the socket is an opening 9 through which the standard 1 passes, and in this opening 9 are rollers 10 which bear against the inner face of the standard 1 adjacent the edges thereof, whereby free movement of the guide on the standard is provided. The upper guide 7 is formed with a socket 11 into which the upper extremity of the standard extends, and the parts are held together by a screw 12. This guide has an opening 13 which has its opposed walls recessed at 14 to receive the lifting element 5. The lifting element 5 is provided at its upper end with a head 15 formed with laterally-projecting and angularly-disposed arms 16 for engaging the object to be raised or moved, and the lower end of the element 5 has a laterally-extend ing object-engaging arm 17 so disposed as to engage the object near the ground.

The lifting element is designed to be lifted on the standard by a rotatable member such as a pinion, and for this purpose, the opposed faces of the standard and element 5 are provided with teeth 18 and 19, whereby the element and standard constitute relativelymovable rack-bars, and meshing with the teeth is a pinion 20 disposed with its axis horizontally between the two rack-bars. This pinion is mounted in a carriage or frame designated generally by A, which is bodily movable on the standard, 1. In the present instance, the carriage comprises a pair of plates 21 and 22 disposed fiat against the opposite sides of the two rack-bars and connected by bolts 23. The pinion 20 has one end squared, as indicated at 24, to receive a large gear wheel 25 disposed at the outside of the plate 22 and inclosed in a casing 26 secured in place by the said bolts 23. The pinion is rotatably mounted by means of journal pins 27 secured to the pinion and passing throu h openings 28 in the plate 21 and wall of t e casing 26.

At one side of the frame or carriage A is a block 29 disposed against the outer face of the standard and fastened to the carriage by two of the bolts 23, the said block form:

ing a bearing for a rotatable shaft 30 which has a pinion 31 meshing with the gear wheel One end of the shaft extends through a hollow boss 32 formed on the casing 26, and the extremity of the shaft is squared at 33 for receiving an operating crank 34 and also a ratchet wheel 35 with which cooperates a gravity-locked pawl 36 pivoted on the bolt 23 above the ratchet wheel, as shown in Fig. 1. The bearing block 29 also constitutes the base portion of a grip or handle 37, whereby the jack can be conveniently carried and placed in position for use.

In order to prevent the bolts from drawing the plates 21 and 22 too tightly together, the bolts :23 atthe side of the jack opposite from the handle 37 are provided with sleeves 38 forming sp'acers, while the block 29 at the handle side of the jack serves the same purpose. On the plates 21 and 22 are mounted disk-shaped rollers 39 carried by screw pivots 40 and arranged to bear against the inner face of the standard, the rack-teeth 18 thereof extending only partially across the said inner face to provide track surfaces etl on which the rollers 39 can ride. It will be noted that the foot piece 3 extends directly under the lifting element, so that the jack will be supported directly in line with the lifting pressure, thus preventing the jack from tilting.

In practice, the jack is positioned in relation to the object to be moved or lifted with the lower or upper arm 16 or 17 in engagement with the object. The operator then turns the crank 34: and thereby causes the lifting element and also the carriage to move upwardly on the standard, the lifting element moving at a greater speed than the carriage. The pawl 36 rides freely on the ratchet wheel as the latter rotates and is always in position to hold the load sustained by the lifting element. hen it is desired to remove the jack, it is merely necessary to release the pawl 36 and allow the crank to turn in the opposite direction to lower the lifting element and carriage. A jack designed in the manner disclosed is capable of exerting a great power and is extremely easy to operate.

From the foregoing description, taken in connection with the accompanying drawing, the advantages of the construction and of the method of operation will be readily apparent to those skilled in the art to which the invention appertains, and while I have described the principle of operation of the invention, together with the apparatus which I now consider to be the best embodiment thereof, I desire to have it understood that the apparatus shown is merely illustrative, and that such changes may be made when desired as are within the scope of the claims appended hereto.

Having thus described the invention, what I claim as new, and desire to secure by Letters Patent, is

1. In a jack, the combination of a pair of oppositely-disposed rack bars, a base on the lower end of one of the rack bars, a device on the upper end of the other rack bar for engaging the device to be moved, a carriage composed of spaced plates engaging opposite sides of the bars, a block arranged between the plates and secured thereto and against which one of the bars slidably bears, sleeves disposed between the plates and with which the other bar slidably engages, said sleeves cooperating with the said block to hold the plates in spaced parallel relation, bolts passing through the sleeves and plates for securing the latter together and for supporting the sleeves, a pinion disposed between the rack bars and meshing therewith,

and means on the carriage for rotating the pinion.

2. In a jack, the combination of spaced parallel rack bars arranged with the teeth of one bar opposite those of the other, a pinion meshing with the teeth of both rack bars, a carriage slidably mounted on the rack bars and supporting the pinion, said carriage having a bearing and including spaced plates engaging the side faces of the rack bars, a handle having abase portion disposed between the plates and provided with a bearing opening disposed in line with the said bearing in the carriage, a rotary shaft mounted in the bearing and opening of the base of the handle, teeth on the shaft, a gear meshing with the teeth and operatively connected with the pinion, and acrank connected with the shaft for turning the same.

3. In a jack, the combination of spaced parallel rack bars, a. carriage consisting of outer plates and an intermediate plate connected by bolts, said rack bars passing between one of the outer plates and the intermediate plate, a bearing on the other outer plate, a bearing block mounted on the carriage in alinementwith said bearing and against one of the rack bars, a shaft rotatably mounted in the bearing block and said bearing, a pinion on the shaft, a gear disposed between the intermediate plate and the outer plate having the bearing to mesh with the pinion on the shaft, a pinion connected with the gear to mesh with the rack bars, and means for rotating the shaft.

4:. In a jack, the combination of a pair of spaced bars, rack teeth thereon, guides for holding the bars in cooperative relation, a pair of plates engaging the bars and bridging the space between them, a pinion rotatably mounted on the plates and engaging the rack-teeth, a bearing block disposed between the plates and engaging the outer face of one of the bars, a crank shaft disposed in the bearing block, a gearing between the crank shaft and pinion, an operating crank on the shaft, a locking device for preventing reverse rotation of the shaft, and a handle secured to the bearing block.

5. In a lifting jack, the combination of a standard, a base piece thereon, a lifting element disposed in spaced relation to the standard, rack teeth on the opposed faces of the standard and lifting element, guides between the element and standard, a carriage composed of plates extending across the standard and element, bolts for securing the plates together, spacing devices on certain of the bolts for spacing the plates apart, a bearing block secured to the plates by the other bolts and engaging the standard, a handle on the bearing block, a crank shaft in the bearing block, a pinion disposed between the plates and meshing with the rack teeth, a gearing between the crank shaft and pinion, a ratchet wheel on the crank shaft, a gravity-locked pawl carried by one of the bolts and engaging the ratchet wheel, an operating crank on the said shaft, anti-friction devices on the plates for engaging the standard, and a device on the lifting element for engaging the objects to be moved.

In testimony, that I claim the foregoing as my own, I have hereto aflixed my signature in the presence of two witnesses.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2852955 *Mar 27, 1953Sep 23, 1958Chavis George DDriving linkage
US3951540 *Sep 25, 1974Apr 20, 1976Minolta Camera Kabushiki KaishaElectrophotographic copier of transfer type
US4541293 *Jun 23, 1982Sep 17, 1985Thomson CsfLoad-bearing telescopic slide assembly and X-ray installation equipped therewith
US4747394 *Oct 8, 1986May 31, 1988Watanabe Orthopedic Systems, Inc.Spinal retractor
US8444114 *Jun 1, 2010May 21, 2013Gilles RivardAnchorage extractor
US20080087788 *Oct 13, 2006Apr 17, 2008Ko-Po ChengHeight adjusting device
US20100301289 *Jun 1, 2010Dec 2, 2010Gilles RivardAnchorage extractor
Cooperative ClassificationB66F3/02