WO2001053709A1

WO2001053709A1 - Brake cable tensioner

Info

Publication number: WO2001053709A1
Application number: PCT/ES2001/000009
Authority: WO
Inventors: Alfonso Cameno Salinas
Original assignee: Batz, S. Coop.
Priority date: 2000-01-20
Filing date: 2001-01-17
Publication date: 2001-07-26
Also published as: ES2160537A1; ES2160537B1; AU3176501A

Abstract

The invention concerns a hand brake cable tensioner, in which an opening part (14) that is fitted with protuberances (26) is placed on the base of the tensioner and engages during opening against two inclined planes of the wedged parts contacting the cable guide. This makes it possible to always separately effectively said guide and the wedged parts.

Description

TENSIONER FOR BRAKE CABLES

DESCRIPTION

OBJECT OF THE INVENTION

The present invention refers to a tensioning element for brake cables of motor vehicles, applicable to the parking or handbrakes that these vehicles are equipped with, which are self-adjusting as regards the cable, in the face of the frequent tension losses of the same that runs from the tensioner to the wheel brakes.

An example of such a tensioner is known from our application EP-A-0 895 909 in which two lateral pieces with wedge ends are placed hugging a slider secured to the cable, the slider and the wedged pieces being provided with a corresponding teeth. The wedge pieces and the slide are embedded inside a closed box with a wedge front outlet end and a rear inlet end on which a piece secured to the slide rests, which serves as a stop to a spring which acts against the wedged side pieces. The closed box is operated by the brake lever.

In the type of tensioner known in this document, it does not contemplate the particular one regarding the solution of a frequent problem in these units, which is that when the vehicle is braked, when the brake lever is lowered and due to external factors on the cable , ice, dirt, for example, there is permanent braking of the assembly as it cannot assure the necessary separation between the slide and the wedged side pieces.

To solve situations like this, document US-A-

4,753,123, which refers to a self-adjusting cable mechanism for clutches or the like, has a threaded slide on which a member acts, which is disconnected from the slide by the action of another part that has a conical extension that acts against a also conical portion of the limb in question. This solution is, however, excessively complicated in its assembly, design and joint operation, since it has a relatively high number of components.

Furthermore, from EP-A-0 754 135 a self-adjusting mechanism with a slide and two wedge pieces is known, in which two different springs intervene, as well as two also different covers and a widened area in the slide.

To undo the connection between the wedged parts and the slide, the two stops are used which act, successively, against the wedged parts and against a connected fork associated with the receiver of the lever arms. In addition to this, the widened pressure of the slide also acts against the wedged parts after the action of the mentioned stops.

This mechanism is relatively complicated by its assembly and by the number of different parts it needs to incorporate.

Aims of the present invention are a self-regulating device for handbrake cables that is simpler and has a low number of components.

Another object of the invention is a self-regulating tensioner for parking brake cables, the assembly of which is convenient and economical.

Another object of the invention is a self-regulating tensioner for handbrake cables that effectively and simply ensures the effective separation of the wedged parts in relation to the slider, avoiding any possibility of permanent braking of the assembly when the brake lever is released.

To carry out these objectives, the invention claims the structural modification of the different components included in the aforementioned EP-A-0 895 909 and the provision of an opening piece for the wedged pieces. Thus, a slider with circular cross-section provided with teeth is established, with a front end in which the cable that goes to the towline, connector ... etc. is fastened, for its arrival at the vehicle wheel brakes. , whose tension of said cable is the one that the set tries to regulate itself.

The rear end of the slide receives a stop piece on which the end of a coil spring that surrounds the slide rests.

The quoted spring is collected between two semi-shells, based on two longitudinal bodies equipped with semi-cylindrical housings and with U-shaped cross sections. The edges of the wings of both bodies are provided with protruding pins and blind holes that receive them. , respectively, so that they can be accommodated with one another by clips, with the particularity that the rear end of the assembly serves as a support for the aforementioned rear slide cover.

Embracing the slide, two lateral wedge-shaped outer pieces are arranged, which are placed facing each other, being provided on the facing faces with semi-cylindrical spaces provided in correspondence with the teeth of the slide.

The two wedged pieces show projections on the top and bottom which are housed with some clearance in corresponding windows made in the front portions of the two longitudinal bodies.

The projections of these two wedged pieces are endowed with respect to a vertical longitudinal median plane of the assembly, an inclination that determines two pairs of inclined planes that offer their surfaces towards the front of the assembly, from their greatest distance to the median plane, up to its smallest distance to said midplane.

For the initial initial assembly at the factory, the spring is placed on the slide, at its rear, positioning the spring stop at the rear end. Next, the two are located in front of the pier wedged parts, so that the spring being under a certain tension, the two outer bodies that clip together are placed on the spring and the wedged parts, whereby the spring and the wedged parts are perfectly pre-assembled.

In this preassembly, the wedged pieces protrude with their projections, up and down, with some clearance, and the top of the spring rests on the rear part of the meeting of the two longitudinal bodies.

According to a preferred solution of the invention, an opening piece of the two wedged pieces is mounted on the slide prior to the placement of the spring, this opening piece having a large hole through which the said slide freely circulates.

The pre-assembled set is subsequently housed inside a generally U-shaped housing whose ends of its wings are bent in contrast.

To carry out the insertion of the previously assembled set inside the cover, two opposite holes are made in the sides of said cover, and in each of the two semi-bodies two pairs of projections, which stand out in the vicinity of the edges of its U-shaped ends so that when connecting the two half-bodies, each two lateral projections are accommodated, finally constituting a joint projection in each of them.

By introducing the pre-assembled set in the cover, each set of projections is received in each lateral hole of said cover by clipping, so that it is carried out very easily.

The cover on its side, is equipped on its sides with facing collars to tie the bottom of the brake lever. Likewise, the front part of said cover is made with a narrowing that configures sloping wedge sides. The slide protrudes logically from this front end of the cover, and the front parts of the two half-bodies between which the wedged parts are housed, also show their outer sides forming a wedge so that they fit perfectly to the front inside of the cover.

Since the spring surrounding the slider acts against the rear vertical walls of the two wedged pieces, the latter are closed on the slider by sliding its outer lateral faces along the inner faces of the narrowing of the cover.

Under normal operating conditions, the cable tension is calibrated and corresponds to that of the spring acting against the clamps.

When the cable is loosened by use, the tension of the spring is greater than that of the cable and thus the spring that is supported by its rear cover, acts on said cover and pulls the slide, providing the new position of the latter the necessary tension to restore the initial balance.

When for external reasons, dirt, ice ... etc., the wedged parts do not get to separate from the slide, so that they leave the assembly in a permanent braking position, the contribution of the opening part always achieves the aforementioned separation in complete safety.

The opening piece is fixed to the support where the handbrake is secured, and it is a vertical piece which at its upper end has at least one horizontal projection that is substantially at the height of the inclined planes formed by the wedged pieces .

Preferably, the opening piece is provided with two parallel projections, one above the height of the two upper inclined planes of the wedged pieces and the other below the height of the lower planes. The ends of the projections are triangular, with rounded corners, and of little thickness, so that when the cover is moved forward actuated by the brake lever, they enter between the inclined planes of the wedged parts, establishing an action of the said projections against said surfaces which is such that they inexorably force the wedged parts to separate in unison from their contact with the slide.

This opening system works perfectly with a piece that includes a single projection to act in relation to the lower inclined planes of the wedged pieces. However, the provision of the part with two projections obviously provides a better and more balanced distribution of efforts.

When the opening part is provided with a single projection, it does not form part of the preassembly of the assembly described above, since the attack on the wedged parts is carried out only from the bottom.

On the contrary, if the opening piece has two projections, it is provided with a hole for the passage of the slide, as previously indicated.

All these and other details of the invention are represented in the accompanying drawing sheets, which are described as follows.

-Figure I ^a , is a perspective of the assembly of the tensioner according to the invention in the ready position for its pre-assembly.

-Figure 2 ^a , represents a perspective of the assembly already assembled with the opening piece affecting the wedged pieces.

-Figure 3 ^a , is an explanatory perspective of the operation of the tensioner.

-Figure 4 ^a , is a perspective of one of the minted pieces.

-Figure 5 ^a , is another perspective of the wedged pieces. -Figure 6 ^a , is a perspective of the opening piece provided with a single projection.

-Figure 7 ^a , finally shows a detail of operation relative to the wedged parts when they are actuated by the tabs of the opening part.

With reference to fig. I ^a , we appreciate the assembly (1) of the tensioner, with the toothed slide (9) that extends longitudinally, including the coil spring (22) with the rear stop (10) and the front end (12) to tie the cable that targets the vehicle's wheel brakes. In this case, the slide incorporates the opening piece (14) with double projection (15).

The two wedged pieces (18) are attached to this slide and below and above the two bodies (2, 3). These two bodies have internal holes (6) to receive the spring (22) and grooves (5) at their front ends (4) to receive the projections, upper and lower (19) of the wedged pieces (18), which enjoy of some slack. The sides of these front portions (4) of the bodies (2, 3) are made in mutual convergence.

The two bodies (2, 3) have pythons at their meeting edges

(7) and blind holes (8) that correspond so that by clip, both bodies are secured. The stop (10) of the spring (22) can establish support at the rear of said bodies, through which the slide and the spring exit.

This set of elements constitutes the preassembly of the tensioner in a stable unit.

In the event that the opening piece (14) does not include more than one projection, the lower one, it is not included in this pre-assembly. It is appreciated that the two bodies (2, 3) are provided with pairs of lateral projections (25), which when closing both bodies, will constitute a joint projection.

The assembly thus made, is subsequently housed inside the cover (11) with a U-section and with the ends of its wings in contrast, which is provided with a front portion (24) that narrows providing internal walls ( 17) wedge, in which the outer faces (21) of the wedged pieces (18) will slide.

To anchor inside the cover (11), it has the lateral holes (16) in which the pairs of projections (25) of the bodies (2, 3) are received by clips.

Also, on the sides the necks (13) in which the lower part of the brake lever will be fixed can be seen.

In this fig. I ^a , the inclined plane surfaces (20) of the projections of the jaws in which the projections (15) of the opening piece (14) will impact are clearly visible.

With respect to fig. 2 ^a , we appreciate how the set of the two bodies (2, 3) and wedged parts is housed in the cover (11), the spring being

(22) extended almost entirely and the tabs of the opening part (14) between the inclined planes of the two wedged parts to open them when the brake lever acts on the cover (11).

Another position different from the set, fig. 3 shows the collected spring, which is seen in greater detail the mutual action between the tabs of the opening piece (14) and the projections of the two pieces minted

(18). It can also be seen how the projections of these two pieces protrude up and down from their entrances in the grooves of the two bodies (2, 3). As noted previously, the opening piece (10) is fixed on the base or support of the assembly by any known means, for example by clipping its four legs (30) in suitable holes in said base.

Each of the wedged pieces (18) of figs. 4 and 5 perfectly shows the configuration thereof with semicircular recesses provided with teeth (23) for arrangement in the slide and the projections (19) suitably shaped to generate the inclined plane (20) to contact the tabs of the opening piece.

When the opening piece has a single tab, fig. 6 ^a , it is located directly on the base of the brake assembly and its contact is made only in relation to the lower projections of the wedged parts. In this particular case, the opening part does not participate in the pre-assembly reflected in fig. I ^a .

According to fig. 7 ^a , the behavior of the wedged pieces (18) when they contact the projections of the opening piece is appreciated. When the end (26) of said part falls between the two parts (18), an effective separation is always made between the teeth (29) of the slide (9) and the teeth (28) of the wedged parts (18), separating both at all times when the brake lever is actuated.

Claims

REINTNDICATIONS

I ^a .- Tensioner for handbrake cables that has a slide (11) connected to the cable, which runs longitudinally associated with two wedged side pieces (18) in the front of a closed box, with the surfaces in contact with the slide and the sides related to corresponding teeth, in which the slide is associated with the cable that runs to the connector and the wedged parts (18) are bound by a spring (22) which, hugging the slide, acts against the mouth of the box through which the slide protrudes, characterized by:

-the slide (11) is circularly toothed circular cross-section and the wedged side pieces (18) have approximately semicircular central recesses (23) corresponding to it, said said wedged side pieces being placed between two upper and lower bodies (2, 3 ) assembled by means of pythons (7) and holes (8) of both, in whose bodies the two coined lateral pieces present the possibility of displacement by having projections (19) in their upper and lower faces that cross corresponding holes (5) of the bodies between those that fit together,

-the upper and lower bodies (2, 3) have a U-shaped mid-section in whose opposite edges are formed the corresponding pythons (7) and holes (8) of mutual connection, flat front portions (4) in those that are made of the aforementioned holes (5) for the minted side pieces (18) and two other semi-cylindrical spaces (6) for the reception of the spring (22) that acts against the minted pieces, resting on the rear front of the assembly of both bodies the stop piece (10) for the spring with which the slide is surrounded,

-a cover (11) of U-shaped cross section open upwards with the ends of its wings tucked inwards, receives the assembly consisting of the bodies (2, 3), spring (22) and wedged parts (18), presenting laterally two protruding and aligned hollow necks (13) for receiving the brake operating lever and, in its front part a narrowing (17) that forms coined sides for the seating of the minted pieces (18),

-the projections (19), upper and lower, of the minted pieces protrude up and down their housings (5) in the bodies

(2, 3) and show inclined plane surfaces (20) accessible from the front part of the assembly through the front part (24) of the cover (11),

-a opening piece (14) of the wedged pieces secured to the base of the brake support, which has at least one surface projection (15) that is at the height of at least one of the planes of the minted pieces in those that the surfaces (20) are made in an inclined plane, the surface projection being finished off by a triangular shaped end (26) of rounded vertex, so that it acts against the two inclined planes of the minted pieces (18).

2 .- tensioner cables handbrake according to I ⁱⁿ claim, characterized in that the projections (19) of minted pieces (18) are housed in recesses (5) of the bodies (2, 3) with some slack

3 .- tensioner cables handbrake according to I and 2nd claims, characterized in that the shape of the projections such plants (19) of the pieces minted and recesses (5) of the bodies (2 , 3) they are in L with an angle covered greater than 90 degrees, one of the sections corresponding to a path parallel to the longitudinal axis of the assembly and the other inclined forming an angle less than 90 degrees with said axis and directed towards the outside of the top.

4 .- tensioner cables handbrake according to I ⁱⁿ claim, characterized in that the opening piece (14) has two surface protrusions (15) to act on the inclined planes (20) of the projections (19) of the two minted pieces (18), said piece (14) being provided with a hole for the passage of the slide. 5 .- tensioner cables handbrake according ^to claim I, characterized in that the opening piece (27) is provided with a single projection surface.

6 .- tensioner cables handbrake according to I ⁱⁿ claim, characterized in the two upper and lower bodies (3) which are provided on both outer sides with respective pairs of projections (25) which are in contact mutual when connecting both bodies, said pairs being received in individual holes (16) provided on the sides of the box (11), by clipping.

7 .- tensioner cables handbrake according ^to claim I, characterized in that the top part (10), the slide (9), the spring (22), the two bodies (2, 3), the two minted pieces (18) and the opening piece (14) with two surface projections (15) constitute a complete unit in the assembly preassembly.