JP2963814B2 - Automatic centering device for tire removal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic centering device, generally associated with a tire removal machine, capable of holding a wheel rim in a horizontal position during tire removal and / or installation operations.

[0002]

2. Description of the Related Art In a conventionally known automatic centering device, a horizontal disk is fixed on an upper part of a vertical concentric shaft arranged below and is driven to rotate by this shaft.

[0003] This disc has a series of identical radially extending openings, usually four, which are equally spaced around the circumference, each of which is usually called a claw, The sliding head is provided for sliding.

The pawls are adapted to be applied to the wheel rim from inside or outside, the alternating approach and / or retreat of said pawls being provided by corresponding connecting rods located below and connected to a common central plate. Done.

The center plate is loosely mounted on a vertical axis of rotation that supports and drives the disk, and is mounted below and in two opposite directions by a plurality of jacks located beside the vertical axis of rotation. Operated to swing.

[0006] Eventually, the opposite ends of the jack are connected to a disk and a normal plate, or to one connection point of the disk and the corresponding connecting rod having a claw. However, the known automatic centering devices described above have proven to be less satisfactory.

The reason for this is that the force required to operate each individual pawl and which is exerted by the jack via the corresponding connecting rod is in the longitudinal direction of the connecting rod, ie in the direction of movement of the corresponding pawl. Acts in an inclined direction, so that only a part of this force (ie the component of the force parallel to the direction of movement of the claw)
Is effectively used to move the nails.

The remainder of this force is largely lost, and the loss is greater when the longitudinal axis of the jack points in a straight line perpendicular to the opening, so that the pawl hits a stop in the corresponding stroke. Tend to try. In addition, dirt accumulates densely over time between the pawl and the stop of the stroke, and the above-mentioned problem gradually becomes prominent, making it difficult for the jack to move the pawl.

In particular, it has been found in any case that the pawls, when acting on the tire installation and / or re-installation tools,
It will cause it to be tightened with insufficient force to hold the locked wheel rim, thereby causing an unexpected interaction between the pawl and the wheel rim and between the wheel rim and the rim and the tool. Movement will occur. Therefore, in such situations, it may be necessary to disassemble the automatic centering device to restore its efficiency.

It is a primary object of the present invention to provide an automatic centering device which can eliminate these disadvantages by having a simple and rational structure.

The automatic centering device according to the present invention comprises a horizontal disk and a rotating shaft fixed to the horizontal disk, which is perpendicular to the axial direction. The horizontal disk has a plurality of openings arranged radially at equal distances. Each groove is associated with a carriage that holds a wheel rim, and each carriage is associated with a connecting rod that is symmetrically disposed with a radially disposed opening, one of the connecting rods being upward. On the rotating plate, the other is associated with the lower rotating plate bearing on the shaft, two connecting rods pivot about a common vertical axis located at the common end in the axial direction of the groove, and a pair of cylinder pistons The unit is provided so as to connect two opposed bases.

In particular, the common vertical axis connecting the two connecting rods crosses the direction of the sliding stroke of the corresponding pawl. Due to the arrangement of the two connecting rods connected via the pawl, there is no possibility that the pawl hits its own sliding stop. An advantage of the present invention is that by applying a force to each carriage in a direction coinciding with the axial direction of the opening in which the carriages move, a thrust is generated such that the carriages can be tilted and pushed out of the openings. That can be avoided. Another advantage is to avoid improper movement while the wheel is held by constantly applying a radial force to the wheel rim via the carriage. Other objects, advantages and features of the present invention will become apparent from the detailed description given below with reference to the accompanying drawings.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, a horizontal disk 1 is driven to rotate by a vertical concentric shaft 2 mounted below. Via known means, the assembly shown is combined with a tire removal machine, but the tire removal machine is not shown for simplicity and may be of any known type.

In a conventional manner, the disc 1 has a series of radially extending openings 3 arranged at regular intervals on the circumference, in this embodiment four openings 3 are provided. A slide 4 (see FIG. 1) is slidably mounted between the openings 3 and has a double-acting pawl 5 on its upper part, that is, the pawl 5 holds the rim 50 of the wheel from inside or outside. It can be locked, while the lower part of the moving table 4 is connected to a plate-shaped slider 6.

In particular, the connection of the carriage 4 with the slider 6 is effected by means of large-sized vertical threaded bolts whose axis intersects the longitudinal axis of the corresponding radial opening 3 (see FIGS. 2 and 3). Will be As shown in FIG. 1, a bush 8 is attached to each bolt 7 below each plate forming the slider 6, and a pair of the same connecting rods 9 are connected to the bush 8. ing.

As for the bolt 7, an intermediate washer 10 is interposed between the two connecting rods 9 (see FIG. 1), while the opposite ends of the connecting rods 9 are two identical square pieces. It is connected to the stacked plates 11.

The two plates 11 are loosely mounted on the vertical rotation shaft 2, and the two connecting rods 9 of different pairs are symmetrically arranged with respect to the moving direction of the corresponding claw 5. In particular, each separate plate 11 is punched, stamped and welded 12
And two thin metal plates connected to each other with a ring-shaped additional element 13 made of tetrafluoroethylene at the center.

Further, the additional element 13 includes an upper shoulder 13 of the shaft 2.
0 (see FIG. 1) and a washer 131 supported by a Seeger ring 132.
The connection between each individual connecting rod 9 and the corresponding plate 11 is made by means of a shaft 70 forming a central pin of different cross-sectional diameter.

In particular, the shaft 70 has two steps forming a central disc-shaped portion and opposing pins, these steps being:
The disc-shaped part projects with respect to the connecting element of the connecting rod 9 and is mutually coaxial with the disc-shaped part, and the pins are accommodated in holes provided in the two strips constituting the plate 11.

Two more pins are riveted between the respective holes. Thus, as shown in the accompanying drawings, the two diametrically opposed plates forming the slider 6 are provided with a pair of downwardly extending side legs 60, which are formed by a projecting orthogonal axis. 66, two corresponding pairs of orthogonal axes are connected by a pneumatic jack 14.

The two jacks 14 are parallel to each other,
It is arranged on both sides of the shaft 2. The operation of the uninvented device will be apparent from the foregoing description and the accompanying drawings.

The advantage of the presence of a pair of connecting rods 9, each acting together on a separate carriage 4, has the effect that this carriage 4 is unlikely to hit a stop in the corresponding stroke. This is due to the fact that the components of the forces acting laterally on the carriage cancel each other, so that only the longitudinal axis component of the opening 3 which is parallel to the movement direction of the carriage is acting on the carriage.

[Brief description of the drawings]

FIG. 1 shows a partial longitudinal section of the device according to the invention.

FIG. 2 is a reduced plan view of the device of FIG. 1 with the rotating disc omitted for clarity and the self-centering device shown in an open position;

FIG. 3 is a view similar to FIG. 2, showing the automatic centering device in a closed position;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Horizontal disk 2 Vertical concentric axis 3 Opening 4 Moving table 5 Double-acting claw 6 Slider 7 Vertically threaded bolt 8 Bush 9 Connecting rod 10 Washer 11 Square plate 12 Welding joint 13 Annular additional element 14 Air jack 50 Wheel rim 60 Side legs extending downward 66 Orthogonal shaft 70 Shaft bar 130 Upper shoulder of shaft 2 131 Washer 132 Seegerling

Claims (2)

(57) [Claims] A horizontal disk (1) and a rotation axis (2) fixed to the horizontal disk (1) and perpendicular to the axial direction, wherein the horizontal disks (1) are equally spaced on the circumference. An automatic centering device for tire removal having a number of radially extending openings (3) arranged, each opening (3) being engaged by a carriage (4) holding a wheel rim (50); Each moving table (4) is connected to connecting rods (9) arranged below the moving table (4) and at symmetrical positions on both sides of the radially extending opening (3), and one of the connecting rods (9) is connected. The upper rotating plate (11) supported on the rotating shaft (2) is connected to the lower rotating plate (11) mounted on the rotating shaft (2), and the two connecting rods (9) have a common end. Pivots around a common vertical axis (7) located in the axial direction of the opening (3), and the two opposing carriages (4) are juxtaposed. Tire removal automatic centering apparatus characterized by being connected by the cylinder piston unit (14) of. 2. A tire removing device comprising the automatic centering device according to claim 1.