BRAKE SHOE

Abstract

A brake shoe is provided including two engagement bodies, where the engagement bodies are connected by a threaded axle, such that by rotating the threaded axle in a first direction around a rotation axis parallel to the axle, the engagement bodies are urged towards each other, and by rotating the axle in a second direction different from the first direction, the engagement bodies are urged away from each other, and where at least one guide axle is provided parallel to the threaded axle, where the two engagement bodies may slide freely along the at least one guide axle, and further where an attachment is provided for attaching the brake shoe to a construction.

Claims

1. A brake shoe comprising: two engagement bodies, where the two engagement bodies are connected by a threaded axle or a bolt, such that by rotating the threaded axle or the bolt in a first direction around a rotation axis parallel to the threaded axle, the two engagement bodies are urged towards each other, and by rotating the threaded axle or the bolt in a second direction different from the first direction, the two engagement bodies are urged away from each other, and where at least one guide axle is provided parallel to the threaded axle or bolt, where the two engagement bodies slide freely along the at least one guide axle, and further where an attachment or means are provided for attaching the brake shoe to a construction and further where the tension in the bolt or the threaded axle is illustrated on a scale, the scale comprising a first part where the tension is below a certain threshold and a second part where the tension is above a certain threshold, and a part between the first and second parts indicating a desired tension.

2. The brake shoe according to claim 1, wherein a strain gauge is mounted on the threaded axle, and where the strain gauge is connected to a control box, which control box may be preprogrammed to indicate the tension in the bolt as a result of the input from the strain gauge.

3. The brake shoe according to claim 2, wherein the tension in the bolt may be illustrated on a scale, the scale comprising a first part where the tension is below a certain threshold and a second part where the tension is above a certain threshold, and a part between the first and second parts indicating a desired tension.

4. The brake shoe according to claim 2, wherein the control box comprises an audible alarm, which alarm is triggered in response to input from the stain gauge, where the input corresponds to a desired tension.

5. The brake shoe according to claim 1, wherein the threaded axle in a first end is provided with a head portion, such that a tool in use may engage the head portion and rotate the threaded axle and thereby apply or reduce a torque to the threaded axle.

6. The brake shoe according to claim 5, wherein the tool is an integrated part of the brake shoe and where the tool may be operated to rotate the threaded axle by manipulating input means.

7. The brake shoe according to claim 6, wherein the input means may be pre-programmed to apply a desired torque to the threaded axle.

8. The brake shoe according to claim 1, wherein the two engagement bodies comprise brake pads, mounted on each engagement body, such that the brake pads face each other, and that orthogonal to and in use below the brake pads, a guide surface is provided on each engagement body.

9. The brake shoe according to claim 1, wherein an upper guide axle is provided in use arranged over the threaded axle, and where a sensor mechanism is provided below the threaded axle, the sensor mechanism comprising a resilient spring arranged between the two engagement bodies urging the two engagement bodies away from each other, an induction or proximity sensor arranged on one engagement body and an adjustable counterpart arranged on the other engagement body, such that the distance may be preset between the induction or proximity sensor and the counterpart.

10. The brake shoe according to claim 1, wherein the threaded axle is a bolt with a built-in tension indicator, where the indicator is visible in the head portion of the bolt, and the indicator is arranged inside the bolt connected to the distal end opposite the head portion, such that as the bolt is tensioned the indicator will visibly indicate when a desired tension is achieved.

11. An extendable conveyor construction comprising a main frame and two or more extendable sections, where each extendable section has one or more lower slide rails, sliding on bearings when the section is being extended or withdrawn, and where a brake shoe comprising two engagement bodies, where the two engagement bodies are connected by a threaded axle or a bolt, such that by rotating the threaded axle or bolt in a first direction around a rotation axis parallel to the threaded axle, the two engagement bodies are urged towards each other, and by rotating the threaded axle or bolt in a second direction different from the first direction, the two engagement bodies are urged away from each other, and where at least one guide axle is provided parallel to the threaded axle or bolt, where the two engagement bodies slide freely along the at least one guide axle, and further where an attachment or means are provided for attaching the brake shoe to a construction and further where the tension in the bolt or the threaded axle is illustrated on a scale, the scale, comprising a first part where the tension is below a certain threshold and a second part where the tension is above a certain threshold, and a part between the first and second parts indicating a desired tension is mounted adjacent one or more of the slide rails on at least one section, such that the brake shoe may be operated to allow the engagement sections to engage and arrest the slide rail, or release the slide rail.

12. The extendable conveyor construction according to claim 11, wherein the brake shoe is mounted on the main frame, such that the guide surfaces engage the slide rail.

13. A method of arresting an extendable section comprising a slide rail, by arranging a brake shoe according to claim 1, such that the guide surfaces of the brake shoe engage the slide rail, and rotating the threaded axle thereby urging the two engagement bodies towards each other, whereby the two engagement bodies engage the slide rail and continue rotating the threaded axle until a strain gauge arranged on the threaded axle indicates that a desired tension is achieved in the threaded axle.

Description

BRIEF DESCRIPTION

[0021] Some of the embodiments will be described in detail, with references to the following Figures, wherein like designations denote like members, wherein:

[0022] FIG. 1 illustrates a brake shoe construction;

[0023] FIG. 2 illustrates a perspective view of the extendable conveyor sections provided with a brake shoe construction;

[0024] FIG. 3 illustrates a side view of an extendable conveyor construction comprising a brake shoe;

[0025] FIG. 4 illustrates a further brake shoe construction;

[0026] FIG. 5 illustrates a further brake shoe construction; and

[0027] FIG. 6 illustrates an example of a Smartbolt which may be used with embodiments of the present invention.

DETAILED DESCRIPTION

[0028] In FIG. 1 is illustrated an example of a brake shoe according to embodiments of the invention. The brake shoe 10 generally comprises two engagement bodies 12,14 where the engagement bodies 12,14 are connected by a threaded axle 16. The engagement bodies 12,14 are provided with threads in the apertures through which apertures the threaded axle 16 passes such that by rotating the threaded axel 16, the engagement bodies 12,14 will be urged towards each other or away from each other, depending on the rotation direction of the threaded axle 16. In this embodiment further two guide axles 18,20 are provided. The guide axles 18,20 are provided in order to assure that the movement of the engagement bodies 12,14 is substantially linear along the axles of the threaded axle. Furthermore, the guide axles 18, 20 are in this embodiment provided with helical springs which will urge the engagement bodies 12,14 apart. This in order to ensure that the brake pads release the object on which they have been engaged when the threaded axle is rotated such that the engagement bodies are urged apart.

[0029] Each engagement body 12,14 is provided with brake pads 22,24 arranged on upper opposing flanges, such that when the brake shoe is arranged around the movable member as will be explained below with reference to FIGS. 2 and 3, the brake pads 22,24 may, by rotating the threaded axle be brought into contact with the movable member. Furthermore, each engagement body 12,14, is provided with guide surfaces 26,28. These guide surfaces 26,28 are arranged below the brake pads 22,24 such that, as will be explained below with reference to FIGS. 2 and 3, the brake shoe is positioned in engagement with the movable member, the guide surfaces will engage the underside of the movable member assuring that the brake shoe is in its correct position.

[0030] Furthermore, the brake shoe 10 is provided with lugs 30,32 on each engagement body. In FIG. 1 only the lugs 30,32 are visible on the right-hand side engagement body 12.

[0031] In an embodiment the threaded axle 16 is in the shape of a bolt provided with a hexagonal head section 34. The head section 34 may be engaged by a regular wrench, thereby rotating the threaded axle 16 bringing the two engagement bodies and the brake pads 22,24 into contact with the movable member which it is desirable to arrest.

[0032] Not illustrated in FIG. 1 is the provision of a strain gauge connected to a control box. However, by arranging a strain gauge on the threaded axle 16, the tension rising in the threaded axle 16, as the engagement bodies engages and clamps the slidable or movable member which it is desirable to brake, the tension mov increase, thereby creating input from the strain gauge which may be transmitted to the control box for further processing.

[0033] Returning to the lugs, 30,32, these are provided in order to be able to bolt the brake shoe 10 on to the machine/apparatus on which it is desirable to arrest a movable member. Typically, the brake shoe 10 will be bolted directly onto the main frame of the apparatus in order to assure that any force arising from movement of the movable/slidable part of the machine is transferred to the strongest part of the apparatus.

[0034] In FIG. 2 is illustrated an extendable conveyor construction comprising a main frame 36 and three extendable conveyor sections 38,40,42. Each conveyor section 38,40,42 is provided with a slide rail 44,46,48. Adjacent each of the slide rails is arranged a brake shoe according to embodiments of the invention as explained above. The brake shoes are encapsulated in a housing such that each brake shoe is mounted on an upper part of the extendable conveyor section below, where only the upper flanges with the brake pads 22,24 extends up and may engage the slide rails 44,46,48. The lowermost brake shoe 10 is arranged on the main frame 36 such that the brake pads may engage the slide rail 44. In order to activate the brake shoe an aperture is provided in the housing such that the head 34 (see FIG. 1) may be accessed through the aperture in order to activate the brake shoe. Similar arrangements are provided for the other brake shoes 10 and 10. Consequently, when desiring to carry out maintenance or repair work on the extendable conveyor construction as illustrated in FIG. 2, all the brake shoes 10, 10 and 10 should be tensioned to the desired tension whereby the brake pads 22,24 are gripping an engaging the guide rails 44,46,48 in such a manner that the extendable members 38,40,42 are not able to move relative to each other. After repair work has finished, the brake shoes may be released by counter rotating the bolt 34 thereby taking the tension out of the threaded axles 16 as explained above.

[0035] Turning to FIG. 3 a closer and detail of the brake shoe arrangements between the movable sections 40 and 42 is illustrated. The upper movable section 42 is extended a little bit relative to the lower section 40. The brake shoe 10 has been activated by assuring that the brake pads 24 are engaging the guide rails 48. In this manner no relative movement is possible between the upper section 42 and the lower section 40 due to the engagement by the brake pads 24 which has been engaged by rotating the threaded axel (see FIG. 1) until they desired tension has been achieved whereby this assured that a solid grip is obtained between the brake pads 24 and the guide rail 48.

[0036] FIGS. 4 and 5 illustrates a further brake shoe construction. In this embodiment only an upper guide axle 52 is provided. The upper axle 52 is in use arranged above the threaded axle 54. In this embodiment the threaded axle is a bolt 54. A sensor mechanism 56 is provided below the threaded axle 54. The sensor mechanism 56 comprises a resilient spring 70 arranged between the two engagement bodies 58,60 urging the engagement bodies 58,60 away from each other. In this embodiment the resilient spring is in the shape of plate springs, but other types of springs such as for example helical springs may be used. An induction or proximity sensor 62 is arranged on one of the engagement bodies 58 and an adjustable counterpart 64 is arranged on the other engagement body 60. By adjusting the distance between the counterpart 64 and the sensor 62 it is possible to determine a preset reading for the proximity sensor 62 which will result in a desired tension. As the bolt 54 is rotated to create the braking tension, the torque necessary to obtain this tension may also be a determining parameter.

[0037] The sensor 62 is connected to a control box (not illustrated) by suitable cabling 65.

[0038] In the illustrated example a bushing 66 is arranged between the engagement bodies 58,60 around the threaded axle 54. The bushing assures that the engagement bodies do not come too close, which may cause the counterpart 64 to engage and possibly damage the sensor 62.

[0039] In use the two engagement bodies 58,60 when not engaging for example a rail on an extendable conveyor section will tilt, such that the brake pads 22,24 (see FIG. 1) will be urged towards each other. This tilt is facilitated by the spring 70. As the bolt 54 is tightened, the brake pads will engage the member they are supposed to fixatefor example a rail on an extendable conveyor. As the brake pads 22,24 engage the rail, the engagement bodies 58,60 will rotate back to a substantially parallel position, whereby the proximity sensor 62 and the counterpart 64 will move linearly towards each other. As the tension in the bolt increases the sensor 62 and the counterpart 64 will move towards each other. At a certain tension the sensor 62 and the counterpart 64 has a mutual distance indicating that the desired tension (brake power) is reached and the sensor (and control box) will be able to indicate this state.

[0040] In FIG. 6 is illustrated an example of a Smartbolt 54 which may be used with embodiments of the present invention. The Smartbolt 54 comprise an inner insert 86 which is integral with the bolt body as such. As the bolt is exposed to tension due to the threaded part 84 engaging a counter-thread, whereby tension is created in the bolt body and thereby in the insert 86. The top of the insert is provided with an indicator 81,82,83. As the tension rises in the bolt 54 the insert 86 is pulled longer. This causes the indicator 81,82,83 to change color. By dimensioning the insert correctly, it is possible to provide a Smartbolt which will change color when a desired tension is achieved. In FIG. 6 the color changes from light gray to black. In reality the color changes from red to black-providing a clear indication that the desired tension and thereby clamping force has been attained. The tension will be directly corresponding to the force the brake pads will exert on the object to be arrestedfor example a rail in an extendable conveyor construction.

[0041] Although the present invention has been disclosed in the form of embodiments and variations thereon, it will be understood that numerous additional modifications and variations could be made thereto without departing from the scope of the invention.

[0042] For the sake of clarity, it is to be understood that the use of a or an throughout this application does not exclude a plurality, and comprising does not exclude other steps or elements. The mention of a unit or a module does not preclude the use of more than one unit or module.