FI113252B - Sleeve connection between outer and inner tube of telescopically adjustable shaft - Google Patents

Description

113252

Sleeve connection between outer and inner tube of telescopically adjustable shaft

The invention relates to a sleeve joint between an outer tube of telescopically adjustable length and an inner tube having a sleeve joint permanently attached to the end of the outer tube and having a tubular joint sleeve having opposing lugs formed in the vicinity of the opening, having a slit formed in the length of the sleeve in the connection sleeve between the fastening lugs and a clamping lever relating to the lugs which is pivotable about a transverse pivot axis relative to the locking wedge surfaces

For example, US 5 585 367 and 15 GB 2 158 865 provide a sleeve joint for connecting an inner and outer pipe to one another. The publications disclose eccentric surfaces which, by rotating the outer sleeve, press the friction pad surfaces against the outer surface of the inner tube. In many applications, for example, the problem with tool arms is to provide sufficient friction locking force quickly, easily, and with little force.

It is an object of the present invention to provide a sleeve joint for a telescopically adjustable tube, which solves the above problem.

The aim is thus to provide a new type of sleeve joint that can withstand considerable axial stress.

This object is accomplished in accordance with the present invention by forming at the end of the clamping lever a pivot axis with tongues which are mated to the counter wedge faces of the clamping lugs, the end surfaces of which form tension wedge surfaces, and which forms the pivot axis of the tensioning rings and which: when pivoting the tensioning rings receives the tensioning forces substantially parallel to the pivot axis, and that the rising wedge surfaces of the pivoting surfaces 2 113252 end in .

Preferred embodiments of the invention are set forth in the dependent claims.

The invention will now be described with reference to the accompanying drawings, in which: Figure 1 is a side view of the sleeve joint and related parts thereof.

Figure 2 shows a top view of a sleeve joint and its associated parts.

Fig. 3 shows the counter wedge surface of the clamping lug.

15

Figure 4 shows a sleeve joint.

Figures 1 and 2 show a sleeve joint in accordance with the present invention and parts thereof. The sleeve connection includes an outer tube designated by reference numeral 1 and an inner tube designated by reference numeral 2. In this embodiment, the tubes are circular. The outer diameter of the inner tube 2 is smaller than the outer diameter of the outer tube: '· *. A slider fit is provided between the tubes 1 and 2 such that: they slide relative to one another. The sliding fit allows the arm to remain rigid at the '· * * joint, even though it is subjected to lateral * · *' forces relative to the arm, thus preventing, for example, buckling.

i / Partly around the other end of the outer tube 1 is provided a sleeve coupling member 30 comprising a sleeve 3, a clamping lever 4 and a pull bar 20. The sleeve 3 is secured; The outer tube 1 is disposed within the sleeve 3 in its axial direction, preferably at a distance of about half the length of the sleeve 3. Thus, the other open end of the sleeve 3 is an axial extension of the outer tube 1, whereby the inner tube 2 can be pushed from the open end of the sleeve 3 into the sleeve connection part 30 and further into the outer tube 1.

3, 113252

In the vicinity of the open end of the sleeve 3, two separate parallel mounting lugs 6a and 6b are formed, the outwardly facing surfaces of which are provided with locking wedge surfaces 5a and 5b. Figure 3 is an axiometric view of the counter-wedge surface 5a of Figure 1 from the top left. The counter wedge surface 5b is otherwise similar in shape but is a mirror image of the longitudinal axis L of the sleeve 3. To simplify the presentation, only the structure and operation of the counter-wedge surface 5a will be explained.

The counter-wedge surface 5a is divided into two radially elevating wedge surfaces 7a, 10a which are radially from about 140 ° to about 170 °. As an extension of the first rising wedge surface 7a, there is formed a latching surface 8a, which is radially short in radius with respect to the rising wedge surface and is inclined in a plane substantially perpendicular to the pivot axis W or downwards in the direction of the clamping force. The outer edge of the latch surface 8a drops downwardly downwardly 15 in the direction of the width axis W, forming a first wedge surface 9a of the counter wedge surface 5a, the lower edge of which is provided by a second rising wedge surface 10a. Similarly, an extension of the wedge surface 10a is formed by a latch surface 11a whose outer edge drops downwardly in the direction of the width axis W to form a second stair surface 12a of the counter wedge surface 5a, which in turn is formed by a first rising wedge surface 7a. An opening 13 is formed in the center of the annular counter wedge surface 5a.

t »* :: A slit 21 is formed in the sleeve 3, between the lugs 6a and 6b, which '. .: extends behind the lips about 1/3 to 2/3 of the length of the sleeve 3, preferably about · · · · 25 about the length of the sleeve 3. The width of the slit 2 is at least twice the height of the step surface 9a, preferably at least four times the height of the step surface 9a.

The sleeve coupling part 30 also includes a separate clamping lever 4, the first of which,. · Two legs 15a and 15b are formed at 30 ends. The ends of the legs 15a and 15b are provided with clamping rings 16a and 16b, the end surfaces of which form relative to each other. i opposing clamping wedge surfaces 17a and 17b. The clamping wedge surfaces 17a and 17b have substantially the same shape as the counter wedge surfaces 5a and 5b.

4, 113252

The clamping lever 4 is secured to the sleeve 3 as shown in Figure 2. The clamping lever 4 is inserted (arrow A) into the clamping lugs 6a and 6b of the sleeve 3 such that the clamping wedge surfaces 17a and 17b of the lever 4 rotate about the counter wedge surfaces 5a and 5b.

5

In the center of the clamping wedge surface 17a is formed an opening 18 through the clamping ring 16a and in the center of the clamping wedge surface 17b is formed an opening 19, which threads are formed on the inner surface of the opening 19. Alternatively, the clamping ring 16b has a recessed nut.

10

The clamping lever 4 mounted in position on the sleeve 3, the clamping lever 4 of the apertures 18 and 19 of the bracket openings 13 in alignment to the screw-threaded pull rod 20 can be inserted in the direction of the arrow shown in Figure 2B by passing accordance with the tow bar 20 an opening 18 and the lugs 15 of the openings 13 through it and tightening it in place on the inner thread of the clamping ring 16b. The longitudinal axis of the draw bar 20 (axis of rotation of the clamping lever) is transverse to the longitudinal axis of the sleeve 3.

Figure 4 illustrates the operation of the clamping lever 4 in different positions of the lever member 14 in Figures I, II and III. Rotation movement of clamping wedge surfaces 17a and 17b of clamping lever 4: '· rotation of the clamping lever 4 extending on the arms 15a and 15b

: '· Using a lever arm 14 or a torque arm. With lever member 14 in position I

: ..: the stair surfaces of the clamping wedge surfaces 17a and 17b rest on the counter wedge surfaces 5a and 5b "· · *, limiting the pivoting of the lever 4,14 to the inner tube 2, whereby the inner tube 2 moves freely. inside the outer tube 1 in the direction of the axis L.

t! »

The clamping wedge surfaces 17a and 17b are rotated with respect to the counter-wedge surfaces 5a and 5b about the axis W (draw bar 20), whereby the clamping wedge surfaces 17a and 17b are pressed against the screw-raising counter-wedge surfaces 5a and 5b. The drawbar 20 also serves to receive the axial tensile forces of the drawbar on the wedge surfaces. When the lever member 4 is in position II, the latch surfaces (not shown) of the clamping wedge surfaces 17a and 17b and the latch surfaces 5 113252 8a, 11a, 8b, 11b of the counter wedge surfaces 5a and 5b begin to overlap and wedge with respect to each other. The clamping force between the latch surfaces is so large that the rotation of the lever member 4 from the intermediate position II to the locking position III occurs essentially by itself. As a result of the torque exerted by the latch surfaces, the lever portion 14 leans against the surface of the outer tube 1 in position III where the longitudinal axis of the lever 4 is substantially the same as the axis L. At the same time, the brackets 6a and 6b are displaced by the split 21 formed between the brackets towards each other by a distance corresponding to the pitch P (height of the stair surfaces) of the counter wedge surfaces 5a and 5b. Correspondingly, the diameter of the end of the sleeve 3 is reduced and this results in a surface pressure between the inner surface of the sleeve 3 and the outer surface of the inner tube 2, which locks the inner tube 2 in place.

The length of the lever member 14 is preferably long relative to the radial distance of the tension wedge surfaces 17a and 17b fla / or counter wedge surfaces 5a and 5b) from the pivot axis 15 20, preferably more than five times, preferably more than eight times. The pivot angle of the clamping lever 4 about the pivot axis W of the draw bar 20 is about 140 ° to 170 °, preferably about 150 ° to 160 °.

The turning angle of the clamping lever 4 may vary depending on the circumferential travel of the clamping wedge surfaces (corresponding to: '20 wedge surfaces') and the latching surfaces, which may also vary as necessary.

• · · • ta <· '; ·; ' The outer end of the clamping lever 4 has gripping cleats which facilitate the manual clamping lever. There is a curved recess between the gripping thickeners corresponding to the curvature of * · · '25 outer tube 1. In this case, in the locking position III of the clamping lever 4, the gripping thickeners are partially or entirely located opposite to the outer tube 1. sides.

: For example, in tool arm use, it is preferable that the outer and inner tubes 1 and 2 have a non-circular, e.g., slightly triangular, cross-sectional shape. triangular-oval shape, whereby the tubes do not rotate about their longitudinal axis with respect to each other and only the axial loads are required to receive the sleeve joint.

Claims (8)

A hollow joint between an outer tube (1) and an inner tube (2) of a telescopic length-adjustable shaft, which hollow joint comprises a hollow joint member (30) which is fixedly attached to the end of the outer tube (1) and which has a tubular joint hollow. (3), in the vicinity of whose opening edge, resilient mounting projections (6a, 6b) are formed, which include radial counter-pitch surfaces (5a, 5b), and between which mounting projections (6a, 6b) in the joint (3) are formed in the hollow (3). elongated slot (21), and clamping levers (4) connected to the fastening projections (6a, 6) which can be rotated about a substantially transverse rotary shaft (W) in relation to the counter shaft surfaces (5a, 5b), characterized in that The ends (15a, 15b) of the clamping lever (4) facing the pivot shaft (4) are formed, the ends of which are fitted with the clamping rings (16a, 16b) of the bracket blades (6a, 5b), adapted end rings (16a, 16b), whose end surfaces form clamping surfaces (17a). , 17b), that the hollow joint portion (30) has a screw thread thereon engaged in the tensioning rings (16a, 16b), engaging pull rod (20), which forms the pivot axis of the tensioning rings (16a, 16b) and which, when turning the tensioning rings (16a, 16b) with the tensioning lever (4), receives the anti-slip surfaces (5a, 5b) directed tensioning forces substantially in the direction of the axis of rotation (W, 20), and that the rising wedge surfaces (7a, 7b) of the counter shaft surfaces (5a, 7b) terminate in the direction of the periphery in the short, transverse axis located relative to the axis (W). in the direction of the clamping force, inclined control surfaces (8a, 8b), which tilt the clamping lever (4) into reading position, are lowered. • · · • · I · • * ·. · · ·. 2. A joint joint according to claim 1, characterized in that the length of the gap (21) is greater than 1/3 and less than 2/3 of the length of the joint holes (3), preferably about half the length of the joint holes (3). 3) length. 3. Jointing joint according to claim 1 or 2, characterized in that the countertop separators (5a, 5b) are divided into two helical ascending surfaces, of which the bed has a: pitch of about 140 ° -170 °. : 30 » 4. Jointing joint according to any one of claims 1 to 3, characterized in that: the angle of rotation of the clamping lever (4) is about 140 ° -170 °, preferably about 150 ° - 160 °. 113252 5. A chuck joint according to any one of claims 1 to 4, characterized in that the length of the clamping lever (4) in comparison with the radial length of the clamping wedges (17a, 17b) and / or the counter plates (5a, 5b) is preferably at least five times, most preferably at least ättafaldig. 5 6. A joint joint according to any one of claims 1 to 5, characterized in that in the loading position of the clamping lever (4), its outer end abuts the outer tube (1). 7. Jointing joint according to any one of claims 1 to 6, characterized in that the outer ends of the clamping lever (4) have gripping thicknesses which, in the reading position of the clamping lever (4), are located partially or completely on the opposite sides of the outer tube (1). Tool shank provided with a hollow joint according to any one of the preceding claims 1 - 7, characterized in that the outer tube (1) and the inner tube (2) have a non-circular intersection which prevents the tubes (1,2) from rotating around its longitudinal axis relative to each other. * «•» · • · ♦ * I t »• · I · • · • I *» · f