US2279465A

US2279465A - Lifting device

Info

Publication number: US2279465A
Application number: US363399A
Authority: US
Inventors: Jackson Alexis
Original assignee: Individual
Current assignee: Individual
Priority date: 1940-10-30
Filing date: 1940-10-30
Publication date: 1942-04-14
Anticipated expiration: 1959-04-14

Description

April 14, 1942. A K 2,279,465

' LIFTING DEVICE Filed Oct. 30, 1940 Fiai 1*) Fica2 a Mo ALEX/6 in c/rso/v INVENTOR.

ATTORNEY Patented Apr. 14, 1942 a it 'i FFECE LIFTING DEVICE Application October 30, 1940, Serial No. 363,399

Claims.

My invention relates to lifting devices and has particular reference to devices for lifting various objects such as automotive vehicles.

In my United States patent application Serial No. 309,324, filed December 15, 1939, patented February 4., 1941, as Patent 2,239,250, I disclosed a lifting jack employing a base mounting pivoted arms, the front ends of the arms being adapted to raise an object such as an automobile axle. The arms are supported on links pivoted at the rear ends to posts on the frame and pivotally connected to blocks slidably mounted on intermediate portions of the arms, A motor is mounted on the arms for moving the sliding blocks, thereby raising the arms.

I have found that for certain purposes it is de sirable to mount the motor directly on the frame or on the rear posts in order to leave the arms free. The sliding blocks can be then moved closer to the rear end, increasing the total movement of the blocks and, therefore, increasing the lift Without lengthening the arms.

In one modification of this device the motor is pivotally mounted on the posts. Although any suitable type of a motor can be used such as electric or hydraulic, I prefer to use an air motor consisting of a cylinder and piston with a piston rod connected to the sliding block. Th cylinder is pivotally mounted on the posts, preferably at its front end so as to make it self-aligning with the piston rod, i. e., with the direction of the force produced by the compressed air in the cylinder.

In another modification of my device, the cylinder is also pivoted to the posts or to the frame, the piston rod being pivotally connected to the intermediate portion of the links, thereby increasing the travel of the sliding block for a relatively short movement of the piston.

In another modification the links are pivotally connected to the intermediate portion of the lifting member, the rear ends of the links being pivotally connected to a block sliding vertically on the upper ends of the posts. The cylinder is mounted on the base, preferably rigidly, the piston rod being connected to the sliding block. In the latter arrangement the piston rod may be also pivoted to the intermediate portions of the links, the cylinder being also pivoted to the frame or to the posts.

My invention is more fully described in the accompanying specification and drawing, in which:

Fig. 1 is an elevational view of my lifting device partly in section;

Fig. 2 is an end View of the same;

Fig. 3 is a top plan view of the same;

Fig. 4 is a detail view 'of a sliding block on a lifting arm of my device;

Fig. 5 is an elevational view of a modified device;

Fig. 6 is an end View of the same;

Fig. 7 is an elevational view of another modification; and

Fig. 8 is an end view of the same.

My lifting device consists of a frame forming a base of my device. It may consist of two side beams 5i joined at the ends by

cross bars

52 and 53 and mounted on wheels 54 rotating on

shafts

55 and 55. The shaft 55 also supports the rear end of a lifting member 51, the front end of the latter being provided with a hook 58 adapted to engage and to support anobject to be lifted, such as an axle of an automotive vehicle.

The frame beams 5| have raised portions or posts 59 at the rear connected at the top by a shaft Bil which supports the upper ends of links Bl The lower or front ends of the links are pivoted at 62 to the sides of a block 63 slidably engaging the upper side of the arm or lifting member 51, which is preferably made in the form of an I-beam. The lifting member 51 can be raised to a position indicated .in dotted lines in Fig. 1 by moving the sliding block 63 forward. This movement can be accomplished by any suitable motor mounted on the raised portions 9 of the frame, but I prefer to use an air motor in the form of a cylinder 64 closed at the rear and open at the front and having a piston 65 sliding inside, the piston being provided with a rod 66 rigidly connected thereto and pivoted on the shaft 62 of the block 63. The cylinder has ears or front extensions 61 supporting trunnions 68 rotatively fitted in the posts 59. Compressed air or other fluid under pressure is delivered to the cylinder by a flexible tube 69 provided with a suitable one-way valve (not shown), if desired.

Due to the location of the pivoting trunnions 68 between the piston 65 and the shaft 62, the cylinder is made self-centering, i. e., it always aligns itself with the piston rod, rotating on its trunnions between the two extreme positions indicated in solid and dotted lines respectively in Fig. 1. The self-aligning feature is further enhanced by mounting the cylinder on extensions or ears 6?, thereby moving the piston farther back of the trunnions.

In a modified construction shown in Figs. 5 and 6, the piston rod 66 is pivoted to the intermediate portions of the links 6! at 1.0, so that a relatively short cylinder can be used for the same movement of the lifting member 51.

In another modification shown in Figs. '7 and 8, the links 6| are permanently pivoted to the intermediate portion of the lifting member 51', the rear ends of the links 6| being pivotally connected to a shaft H whose ends slide in slots 12 provided in the upper portions of rear posts or frame extensions 13, connected at the top by a cross bar M.

The lifting member is raised by moving the shaft H upward in the slots 12. This movement can be conveniently accomplished by an air motor consisting of a cylinder 15 rigidly mounted on the frame between the posts 13. A piston 65 slides in the cylinder and is provided with a rod 65 pivoted to the middle portion of the shaft H.

It should be noted that the links El can be connected into a single link member, i. e., they can be integrally joined together into a single element. Similarly the two posts 59 or 13 can be integrally joined together into a single member.

It is understood that my lifting device may be further modified without departing from the spirit of this invention, as set forth in the appended claims.

I claim as my invention:

1. A lifting device comprising a frame forming a base having a raised rear portion, a lifting member having its rear end pivotally supported at the rear portion of the frame, the front end of the lifting member being adapted to raise a load, a link member extending in tension between the raised portion of the frame and lifting member, one end of the link member being pivoted and the other end having a sliding connection, and a motor interposed between the frame and the intermediate portion of the link member for moving the sliding connection, thereby raising the lifting member.

.2. A lifting device comprising a frame forming a base having a raised rear portion, a lifting member having its .rear end pivotally supported at the rear portion of the frame, the front end of the lifting member being adapted .to raise a load, a link member extending between the raised portion of the frame and lifting member, one end of the link member being pivoted to th raised portion of the frame and the other end having a sliding connection with the lifting member, and means on the frame for moving the sliding connection, thereby raising the lifting member,

3. A lifting device comprising a frame forming a base having a raised rear portion, a lift- 1 ing member having its rear end pivotally supported at the rear portion of the frame, the front end of the lifting member being adapted to raise a load, a link member extending in tension between the raised portion of the frame and lifting member, one end of the link memher being pivoted and the other end having a sliding connection, and a motor pivotally supported on the frame engaging the intermediate portion of th link member for moving the slidto raise a load, .a link member extending between the raised portion of the frame and lifting member, one end of the link member being pivoted to the raised portion of the frame and the other end having a sliding connection with the lifting member, a cylinder having an open and a closed end pivotally connected to the raised portion of the frame at its open end and extending rearward of the frame, a piston in the cylinder, and extending from the piston pivotally connected to the sliding connection, and means to admit a fluid under pressure into the cylinder, thereby raising the lifting member.

5. A lifting device comprising a frame forming a base having a raised rear portion, a lifting member having its rear end pivotally supported at the rear portion of the frame, the front end of the lifting member being adapted to raise a load, a link member extending between the raised portion of the frame and lifting member, one end of the link member being pivoted to the raised portion of the frame and the other end having a sliding connection with the lifting member, and means on the frame for raising the link member, thereby raising the lifting member.

6. A lifting device comprising a frame forming a base having a raised rear portion, a lifting member having its rear end pivotally supported at the rear portion of the frame, the front end of the lifting member being adapted to raise a load, a link member extending between the raised portion of the frame and lifting member, one end of the link member being pivoted to the raised portion of the frame and the other end having a sliding connection with the lifting member, a cylinder having an open and a closed end mounted on the frame, a piston slidably fitted in the cylinder, a rod extending from the piston pivotally connected to the intermediate portion of the link member, and means to admit a fluid under pressure into the cylinder for raising the lifting member.

'7. A' lifting device comprising a frame forming a base having a raised rear portion, a lifting member having its rear end pivotally supported at the rear portion of the frame, the front end of the lifting member being adapted to raise a load, a link member extending between the raised portion of the frame and lifting member, one end of the link member being pivoted to the raised portion of the frame and the other end having a sliding connection with the lifting member, and a motor on the frame operatively connected with the sliding end of the link for moving the sliding connection, thereby raising the lifting member.

8. A lifting device comprising a frame, posts at the rear of the frame, a lifting member pivotally connected to the rear portion of the frame, the front end of the lifting member being adapted to raise a load, a block slidably sup- ..ported on the lifting member, links pivotally connected to the block and to the upper ends of the posts, a motor on the frame, and means to move the block by the motor, thereby raising the lifting arms.

9. A lifting device comprising a frame, posts at the rear of the frame, a lifting member pivotally connected to the rear portion of the frame,

the piston pivotally connected with the block, and means to admit a fluid under pressure into the cylinder for raising the lifting member.

- 10. A lifting device comprising a base, an arm member pivotally supported on said base and adapted to support a load at its movable end, a post member rigidly mounted on said base and extending upwardly, said arm member having a guideway, said post member having a pivot device, a carrier on said guideway, a motor for moving said carrier along said guideway, and a bar connected at one end to said pivot device and at the other end to said carrier, whereby raising said carrier causes the movable end of said arm member to b raised.

ALEXIS JACKSON.