Four-post hoist

A hoist for lifting vehicles such as automobiles, trucks, and so forth, comprising:

• at least four vertically extending posts, the posts defining a quadrilateral, one post being placed at each corner of the quadrilateral;
• a lifting frame having portions positioned within the quadrilateral, the lifting frame being engageable with portions of a vehicle so as to raise and lower the vehicle, the lifting frame being vertically slidably connected to each of the posts;
• a first brace extending between and connected to a given pair of posts, a second brace extending between and connected to the other pair of posts, the braces, when viewed from above, being parallel with each other and lying generally along the boundary of the quadrilateral defined by the posts, the braces being connected to the posts toward the upper end of the posts;
• a plurality of drive means for raising and lowering the lifting frame, a separate drive means being provided for each corner of the lifting frame and being connected to each corner of the frame by means of a flexible connection, two drive means being secured to the first brace and two driving means being secured to the second brace;
• each drive means comprising a hydraulic cylinder having an extensible actuating rod;
• each flexible connection comprising a chain connected at one end to the rod and connected at the other end to the frame, the chain passing over a pulley located at or near the upper end of each post;
• a plurality of sliding blocks connected to the braces, one sliding block being provided for each hydraulic cylinder, the blocks being slidable along the braces and carrying the end of the actuating rods and the connection with the chains.

A relatively inexpensive, rapidly constructed hoist for lifting vehicles such as automobiles, trucks, and so forth, comprising:

• vertically extending posts, each post being placed at the corner of an area in the shape of a quadrilateral, each post being in the form of an H-beam, the flanges of the H-beam defining channels;
• a lifting frame disposed largely within the area defined by the quadrilateral, the lifting frame including a pair of crosspieces formed of I-beams, the crosspieces when viewed from above being parallel with each other and extending between and coming in contact with channels of separate pairs of posts, the lifting frame also including a pair of generally parallel runways formed of I-beams, the runways resting atop and being carried by the crosspieces, the runways when viewed from above being substantially perpendicular to the crosspieces;
• a pair of braces connecting the posts, the braces being in the form of H-beams, the braces being secured to the posts on the outer surface of the flanges defining the channels;
• a lifting mechanism, the lifting mechanism being connected to the corners of the frame whereby, upon actuation of the lifting mechanism, the frame is raised and lowered as desired;
• the lifting mechanism including a pair of drive means secured to each brace, the drive means being connected to separate ends of the crosspieces, the connections being made by a flexible connection extending from the drive means to and around a pulley secured at or near the upper end of each post.

An inexpensive, rapidly assembled pulley for efficiently changing the direction of force applied by a chain, comprising:

• a first pair of disc-like plates, each of the first pair of plates having an opening at its center;
• a second pair of disc-like plates, each plate having an outer diameter smaller than the outer diameter of the first pair of plates, each of the second pair of plates also having an opening at its center, the second pair of plates, in use, having their openings positioned coaxially with respect to the openings in the first pair of plates, the second pair of plates being compressed between the first pair of plates;
• and,
• a third disc-like plate, the third plate including an opening at its center, the third plate having an outer diameter smaller than the outer diameter of the second pair of plates, the third plate being compressed, in use, between the second pair of plates and having its central opening positioned coaxially with respect to the openings in the second pair of plates.

A hoist for lifting vehicles such as automobiles, trucks, and so forth, comprising:

• four vertically extending posts, the posts defining a rectangle with one post being placed at each corner of the rectangle, the posts being in the form of H-beams having channel-defining flanges;
• a lifting frame disposed largely within the area defined by the rectangle, the lifting frame including a pair of crosspieces formed of I-beams, the crosspieces when viewed from above being parallel with each other and extending between and coming in contact with channels of separate pairs of posts, the lifting frame also including a pair of generally parallel runways formed of H-beams, the runways resting atop and being carried by the crosspieces, the runways when viewed from above being substantially perpendicular to the crosspieces;
• a pair of braces connecting the posts, the braces being in the form of H-beams, the braces being secured to the posts on the outer surface of the flanges defining the channels, the braces being parallel with the longer sides of the rectangle;
• and,
• a lifting mechanism, the lifting mechanism being connected to the ends of the crosspieces whereby, upon actuation of the lifting mechanism, the frame is raised and lowered as desired, the lifting mechanism including:
• hydraulic cylinders having extensible actuating rods, two hydraulic cylinders being secured to each brace and connected to a different crosspiece;
• a flexible connection between each actuating rod and an end of a crosspiece, the flexible connection being in the form of a chain passing over a pulley, the pulley being located at or near the upper end of a post;
• and,
• a plurality of sliding blocks connected to the braces, one sliding block being provided for each hydraulic cylinder, the blocks being slidable along the braces and carrying the ends of the actuating rods and the connection with the chains.