Rotation Sensor Assemblies and Methods of Use

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of and priority to Danish Application No. PA 2024 30313, filed Jun. 11, 2024, which is hereby incorporated by reference in its entirety.

FIELD OF INVENTION

The present invention relates to rotation sensor assemblies suitable for being used in construction vehicles.

BACKGROUND

Excavators are digging machines, typically mounted on tracks or wheels. A typical excavator has a bucket mounted to the end of a two-member linkage or a three-member linkage. When the excavator has a bucket mounted to the end of a two-member linkage, one of the links, called a boom (swing arm), is pivotally mounted to a mounting structure of the excavator and extends outward in an upward direction. The other link, typically referred to as a stick, is pivotally mounted at one end to the outer end of the boom and extends downward from the boom pivot.

When the excavator has a bucket mounted to the end of a three-member linkage, a first boom is pivotally mounted to a mounting structure of the excavator and extends outward in an upward direction. A second boom is rotatably mounted to the distal end of the first boom and extends between the first boom and a stick being pivotally mounted at the distal of the second boom. In some constructions, the stick is provided as a telescopic arm.

To control the boom, stick and bucket in an accurate manner, it is required to be able to detect the relative rotational motion and/or angle (angular position) between the boom and the cap in an accurate manner.

EP3884114A1 discloses a position detection device for detecting the position of a bucket of an excavator having a cab and an arm comprising one or more booms, wherein the arm comprises a first boom being rotatably attached to the cab by a mounting structure that is rotatably attached to the cab by a shaft having a longitudinal axis extending basically vertically during normal use. A wire sensor is used to detect the rotation of the first boom about the longitudinal axis of the shaft. It is, however, challenging to calibrate the wire sensor.

WO2024090014A1 discloses a swing angle calibration method and a swing angle calibration system. The swing angle calibration system comprises a swing angle sensor connected to a swing bracket by a link mechanism. It is, however, challenging to adjust the swing angle calibration system. Accordingly, it would be advantageous to be able to provide a solution that is more flexible and easier to adjust.

Thus, there is a need for a rotation sensor assembly that is flexible and easier to adjust and is capable of detecting the relative rotational motion and/or angle (angular position) between the boom and the cap in an accurate manner without requiring a challenging calibration.

BRIEF DESCRIPTION

In an embodiment, a rotation sensor assembly disclosed herein comprises a first portion and a fixation member,

• • wherein the first portion is configured to be attached to a cap of an excavator,
  • wherein the fixation member is configured to be attached to a boom of the excavator,
  • wherein the first portion comprises an angle bracket attached to a base bracket having a foot portion,
  • wherein a plurality of slots is provided in an upper portion of the base bracket, each slot being configured to receive a portion of a bolt extending through the slot for detachably attaching the base bracket to a first part of the angle bracket,
  • wherein the angle bracket comprises one or more slots each configured to receive a bolt extending through a slot of the base bracket and the slot of the angle bracket,
  • wherein the first portion comprises a magnetic sensor base, wherein a magnetic sensor portion is attached to the fixation member,
  • wherein the sensor base is attached to the angle bracket,
  • wherein the rotation sensor assembly is arranged and configured to detect the angular position and/or angular motion of the sensor portion relative to the sensor base.

Hereby, it is possible to ensure that the sensor mounting member and the sensor portion are aligned and arranged sufficiently close to each other to ensure that a magnetic field with a sufficiently large amplitude can be detected when applying the rotation sensor assembly. Accordingly, the rotation sensor assembly is capable of detecting the relative rotational motion and/or angle (angular position) between the boom and the cap in an accurate manner.

The rotation sensor assembly is configured to detect the relative rotational motion and/or angle (angular position) of a boom of an excavator in an accurate manner.

The rotation sensor assembly comprises a first portion configured to be attached to the cab of an excavator. The first portion comprises one or more structures for mounting a sensor portion of the rotation sensor assembly. The first portion comprises one or more structures for attaching the first portion to the cab of the excavator.

The first portion comprises an angle bracket attached to a base bracket having a foot portion, wherein a plurality of slots is provided in an upper portion of the base bracket, each slot being configured to receive a portion of a bolt extending through the slot for detachably attaching the base bracket to a first part of the angle bracket.

The angle bracket comprises one or more slots each configured to receive a bolt extending through a slot of the base bracket and the slot of the angle bracket.

The first portion comprises a magnetic sensor base, wherein a magnetic sensor portion is attached to the fixation member, wherein the sensor base is attached to the angle bracket, wherein the rotation sensor assembly is arranged and configured to detect the angular position and/or angular motion of the sensor portion relative to the sensor base.

In an embodiment, the rotation sensor assembly comprises a protection member configured to be attached to a boom of the excavator. In an embodiment, the protection member comprises a protection top member and a protection bottom member that is detachably attached to the protection top member.

In an embodiment, the rotation sensor assembly comprises a protection member comprising a protection top member, wherein the fixation member is a protection bottom member that is detachably attached to the protection top member.

In an embodiment, the sensor portion is a transmitter whereas the sensor base is a receiver.

In an embodiment, the sensor base is a transmitter whereas the sensor portion is a receiver.

In an embodiment, the rotation sensor assembly comprises a sensor base and a sensor portion, wherein the sensor portion comprises a cavity in which cavity a male portion is rotatably mounted, wherein the rotation sensor assembly is arranged and configured to detect the angular position and/or angular motion of the sensor base relative to the male portion of the sensor portion.

In an embodiment, the angle bracket is L-shaped.

In an embodiment, a nut is fixed to each bolt to attach the base bracket and the angle bracket to each other.

In an embodiment, the slots of the base bracket extend perpendicular to the slot(s) of the angle bracket.

In an embodiment, the protection top member comprises an angled portion that is integrated to form a one-piece body having a V-shaped profile.

In an embodiment, the protection top member comprises an angled portion that is integrated to form a one-piece body having an L-shaped profile.

In an embodiment, the protection member comprises a detachably attached reinforcement member extending between the protection top member and the protection bottom member.

Hereby, the reinforcement member reinforces the protection member by enhancing the compressive strength of the protection member.

In an embodiment, the reinforcement member is U-shaped.

In an embodiment, the reinforcement member has two flange portions extending between a planar portion that is attached to the angled portion.

In an embodiment, the reinforcement member has two parallel flange portions extending between a planar portion that is attached to the angled portion.

In an embodiment, the parallel flange portions extend perpendicular to the planar portion.

In an embodiment, the planar portion is attached to the angled portion using bolts.

In an embodiment, the bolts extend through holes provided in the planar portion of the reinforcement member.

The protection member is configured to protect the sensor mounting member and the sensor portion as well as other components (e.g. a hydraulic hose and/or a hydraulic sensor) placed between the protection top member and the protection bottom member.

In an embodiment, the first portion comprises a top bracket that is detachably attached to a second part of the angle bracket.

In an embodiment, the top bracket is detachably attached to the second part of the angle bracket using bolts extending through the slots of the top bracket, wherein the slots provided in an upper portion of the base bracket and the one or more slots provided in the angle bracket are arranged in such a manner that the angle bracket can be rotated relative to the base bracket. The use of this slot configuration has the surprising effect of making it possible to rotate the angle bracket relative to the base bracket.

In an embodiment, each bolt is screwed into a threaded bore provided in the top bracket.

In an embodiment, a plurality of threaded bores is distributed along the length of the top bracket. Hereby, the second part of the (typically L-shaped) angle bracket may be attached to different threaded holes in order to achieve a desired degree of overlap between the second part of the L-shaped angle bracket and the top bracket.

In an embodiment, the first portion comprises a top bracket detachably attached to the angle bracket.

In an embodiment, the first portion comprises a sensor base that is attached to the top bracket.

In an embodiment, the sensor base is attached to the top bracket using screws or bolts extending through through-bores provided in the sensor base.

In an embodiment, the sensor base comprises a socket arranged and configured to be electrically connected to a cable provided with an electric plug.

In an embodiment, the fixation member is a sensor mounting member provided with a threaded rod or bolt protruding from a bottom surface of the sensor mounting member.

In an embodiment, the threaded rod or bolt is centrally arranged and protrudes from the bottom surface of the sensor mounting member.

In an embodiment, the threaded rod or bolt is configured to be screwed into a threaded hole of the boom of an excavator, while the sensor portion and the top bracket of the first portion is attached to the cab of the excavator. Hereby, the rotation sensor assembly can detect the angular position and/or angular motion of the boom of an excavator relative to the cab of the excavator.

In an embodiment, the threaded rod or bolt is configured to be screwed into a threaded hole of the cab of an excavator, while the sensor base and the top bracket of the first portion are attached to the boom of the excavator. Hereby, the rotation sensor assembly can detect the angular position and/or angular motion of the boom of an excavator relative to the cab of the excavator.

In an embodiment, the sensor base is attached to the top bracket. In an embodiment, the fixation member is a protection bottom member.

The excavator, according to an embodiment, is an excavator comprising a rotation sensor assembly as disclosed herein, wherein the first portion is attached to a cab of the excavator whereas the fixation member is attached to the boom of the excavator.

Alternatively, the first portion is attached to the boom of the excavator whereas the fixation member is attached to the cab of the excavator.

Hereby, the excavator can, by using the rotation sensor assembly, detect relative rotational motion and/or angular positions between the boom of an excavator and the cap of the excavator. By using an excavator provided with a rotation sensor assembly according to the present disclosure, it is possible to ensure that the fixation member and the sensor portion are aligned and arranged sufficiently close to each other to ensure that a magnetic field with a sufficiently large amplitude can be detected when applying the rotation sensor assembly.

A method according to the present disclosure is a method for mounting a rotation sensor assembly on an excavator, the rotation sensor assembly comprising a first portion and a fixation member,

• • wherein the first portion is configured to be attached to a cap of the excavator, wherein the fixation member is configured to be attached to a boom of the excavator, wherein the first portion comprises an angle bracket attached to a base bracket having a foot portion,
  • wherein a plurality of slots is provided in an upper portion of the base bracket, each slot being configured to receive a portion of a bolt extending through the slot for detachably attaching the base bracket to a first part of the angle bracket,
  • wherein the angle bracket comprises one or more slots each configured to receive a bolt extending through a slot of the base bracket and the slot of the angle bracket,
  • wherein the first portion comprises a magnetic sensor portion,
  • wherein a sensor portion is attached to the fixation member,
  • wherein a sensor base is attached to the angle bracket,
  • wherein the rotation sensor assembly is arranged and configured to detect the angular position and/or angular motion of the sensor portion relative to the sensor base.

BRIEF DESCRIPTION OF THE DRAWINGS

The assemblies and methods will become more fully understood from the detailed description given herein below. The accompanying drawings are given by way of illustration only, and thus, they are not limitative. In the accompanying drawings:

FIG. 1A shows a perspective rear view of a rotation sensor assembly according to an embodiment comprising a first portion and a protection member;

FIG. 1B shows a side view of a first portion basically corresponding to the one shown in FIG. 1A;

FIG. 2A shows a perspective rear view of a rotation sensor assembly basically corresponding to the one shown in FIG. 1A;

FIG. 2B shows another perspective rear view of a rotation sensor assembly basically corresponding to the one shown in FIG. 1A;

FIG. 3A shows an exploded view of a protection member of a rotation sensor assembly according to an embodiment;

FIG. 3B shows the protection member of the rotation sensor assembly shown in FIG. 3A in an assembled configuration;

FIG. 3C shows an exploded view of a protection member of a rotation sensor assembly according to an embodiment;

FIG. 3D shows the protection member of the rotation sensor assembly shown in FIG. 3C in an assembled configuration;

FIG. 4A shows an exploded view of a first portion of a rotation sensor assembly according to an embodiment;

FIG. 4B shows the first portion of the rotation sensor assembly shown in FIG. 4A in an assembled configuration;

FIG. 4C shows another view of the first portion of the rotation sensor assembly shown in FIG. 4A in an assembled configuration;

FIG. 5A shows an exploded view of a protection member of a rotation sensor assembly according to an embodiment;

FIG. 5B shows the protection member of the rotation sensor assembly shown in FIG. 5A in an assembled configuration;

FIG. 6A shows a side view of an excavator according to an embodiment;

FIG. 6B shows a perspective front view of the excavator shown in FIG. 6A;

FIG. 7A shows how the sensor components may be aligned;

FIG. 7B shows the sensor components illustrated in FIG. 7A in an assembled configuration;

FIG. 8A shows how the sensor components may be aligned;

FIG. 8B shows a perspective top view of the sensor components illustrated in FIG. 8A in an assembled configuration mounted to a top bracket;

FIG. 8C shows a side view of the sensor components illustrated in FIG. 8B;

FIG. 9A shows a close-up view of the area of an excavator in which a rotation sensor assembly according to an embodiment has to be mounted;

FIG. 9B shows a close-up view of a fixation member attached to the boom of the excavator shown in FIG. 9A;

FIG. 10A shows a first step of a method according to an embodiment;

FIG. 10B shows a second step of a method according to an embodiment;

FIG. 10C shows a third step of a method according to an embodiment;

FIG. 10D shows a fourth step of a method according to an embodiment;

FIG. 10E shows a fifth step of a method according to an embodiment;

FIG. 11A shows a side view of a rotation sensor assembly according to an embodiment; and

FIG. 11B shows how to adjust the angles of the rotation sensor assembly.

DETAILED DESCRIPTION

Referring now in detail to the drawings for the purpose of illustrating embodiments of the present assemblies and methods, a rotation sensor assembly 2 is illustrated in FIG. 1A.

FIG. 1A illustrates a perspective rear view of a rotation sensor assembly 2 according to an embodiment. The rotation sensor assembly 2 comprises a first portion 4 and a protection member 6. FIG. 1B illustrates a side view of a first portion 4 basically corresponding to the one shown in FIG. 1A.

The first portion 4 is designed and configured to be attached to the cap of an excavator. The protection member 6 is designed and configured to be attached to a boom of an excavator.

The first portion 4 comprises an L-shaped angle bracket 18 and a base bracket 10 having a foot portion 8 provided with two feet. A plurality of slots 12 are provided in the upper portion of the base bracket 10. Theses slots 12 are configured to receive bolts 16 extending through the slots 12 for detachably attaching the base bracket 10 to a first part of the L-shaped angle bracket 18.

The L-shaped angle bracket 18 comprises a plurality of slots 12′ configured to receive bolts 16 extending through the slots 12 of the base bracket 10 and the slots 12′ of the angle bracket 18. A nut 14 is fixed to each bolt 16 to attach the base bracket 10 and the angle bracket 18 to each other in a firm and reliable manner. In an embodiment, the slots 12 of the base bracket 10 extend perpendicular to the slots 12′ of the angle bracket 18.

The first portion 4 comprises a top bracket 20 that is detachably attached to the second part of the L-shaped angle bracket 18 by bolts 16 extending through the slots 12″ of the top bracket 20. Each bolt 16 is screwed into a threaded bore 11 provided in the top bracket 20. A plurality of threaded bores 11 are distributed along the length of the top bracket 20. Accordingly, the second part of the L-shaped angle bracket 18 may be attached to different threaded holes 11 in order to achieve a desired degree of overlap between the second part of the L-shaped angle bracket 18 and the top bracket 20.

In an embodiment, the plurality of threaded bores 11 is distributed along two parallel spaced apart lines extending along the length of the top bracket 20. In an embodiment, the top bracket 20 is provided with a single slot 12″ extending along the length of the top bracket 20.

The first portion 4 comprises a sensor base 22 that is configured to be attached to the top bracket 20. The top bracket 20 is provided with threaded holes 11. The sensor base 22 is provided with through-going holes. Accordingly, the sensor base 22 can be attached to the top bracket 20 by inserting bolts through the holes of the sensor base 22 and screwing the bolts into the threaded holes 11. This can be seen in FIG. 4A.

The sensor base 22 comprises a socket 36 arranged and configured to be electrically connected to a cable provided with an electric plug.

The sensor base 22 is configured to receive and hereby provide an easy way of attaching the sensor portion 24 to the sensor base 22. Hereby, it is possible to attach the sensor portion 24 to the top bracket 20 of the first portion 4.

In FIG. 1B a sensor mounting member 26 is arranged below and bears against the sensor portion 24. Both the sensor mounting member 26 and the sensor portion 24 are cylindrical. In an embodiment, the sensor mounting member 26 and the sensor portion 24 have the same diameter.

In order to detect relative rotational motion and/or angular positions between the boom of an excavator and the cap of the excavator, the sensor mounting member 26 and the sensor portion 24 have to be aligned and be arranged close to each other as the magnetic field decreases with the distance to the power of three.

The sensor mounting member 26 is provided with a threaded rod 28 protruding from the bottom surface of the sensor mounting member 26. It may be advantageous that the threaded rod 28 is centrally arranged and protrudes from the bottom surface of the sensor mounting member 26.

In an embodiment, the threaded rod 28 is configured to be screwed into a threaded hole of the boom of an excavator, while the sensor portion 24 and the top bracket 20 of the first portion 4 are attached to the cab of the excavator. Hereby, the rotation sensor assembly 2 can detect the angular position and/or angular motion of the boom of an excavator relative to the cab of the excavator.

In an embodiment, the threaded rod 28 is configured to be screwed into a threaded hole of the cab of an excavator, while the sensor portion 24 and the top bracket 20 of the first portion 4 are attached to the boom of the excavator. Hereby, the rotation sensor assembly 2 can detect the angular position and/or angular motion of the boom of an excavator relative to the cab of the excavator.

The protection member 6 comprises a protection bottom member 30 provided with two parallel mounting portions 32 each provided with a hole 34. The holes 34 can be used to attach the protection member 6 to a boom of an excavator.

The protection member 6 comprises a protection top member 40 and an angled portion 42 that are integrated to form a one-piece body having a V-shaped profile. The angled portion 42 is detachably attached to the protection bottom member 30.

The protection member 6 comprises a reinforcement member 38 extending between the protection top member 40 and the angled portion 42. Hereby, the reinforcement member 38 reinforces the protection member 6 by enhancing the compressive strength of the protection member 6. The reinforcement member 38 may be U-shaped and have two parallel flange portions extending between a planar portion that is attached to the angled portion 42 e.g. by using bolts (see FIG. 3A, FIG. 3B and FIG. 3C). The bolts may extend through holes 46 provided in the planar portion of the reinforcement member 38.

The protection member 6 is configured to protect the sensor mounting member 26 and the sensor portion 24 as well as other components (e.g. a hydraulic hose and/or a hydraulic sensor) placed between the protection top member 40 and the protection bottom member 30.

FIG. 2A illustrates a perspective rear view of a rotation sensor assembly 2 basically corresponding to the one shown in FIG. 1A. FIG. 2B illustrates another perspective rear view of a rotation sensor assembly 2 basically corresponding to the one shown in FIG. 1A.

The rotation sensor assembly 2 comprises a protection member 6 that slightly differs from the one shown in FIG. 1A. The protection member 6 comprises a protection top member 40 having an edge portion provided with an indentation (e.g. for receiving a hose or a cable). The protection bottom member 30 comprises a planar mounting portion 32 provided with two parallel and spaced apart slots 34. It may be an advantage that the slots 34 extend perpendicular to the length of the angled portion 42.

FIG. 3A illustrates an exploded view of a protection member 6 of a rotation sensor assembly according to an embodiment. The protection member 6 comprises a protection bottom member 30 provided with two slots 34 and a plurality of mounting holes 50, 50′. The protection bottom member 30 comprises a planar portion and a bent portion 52 protruding perpendicular from the planar portion.

The protection bottom member 30 comprises two female portions 44 each configured to receive a male portion (protruding member) 54 of the protection top member 40 of the protection member 6.

The bent portion 52 comprises threaded holes 58 each configured to receive a threaded portion of a bolt 16.

The protection member 6 comprises a protection top member 40 having a L-shaped profile. The protection top member 4 comprises a planar portion and an angled portion 42 protruding from the planar portion. The angled portion 42 comprises two threaded holes 56 each configured to receive the threaded portion of a bolt 16.

The protection member 6 comprises a reinforcement member 38 shaped as a U-shaped one-piece body provided with holes 46. The reinforcement member 38 is configured to be attached to the angled portion 42 by inserting bolts 16 through the holes 46 in the reinforcement member 38 and screwing the bolts 16 into the threaded holes 56 in the angled portion 42.

In an embodiment, the holes 46 have an elongated shape in order to ease the attachment of the reinforcement member 38 to the angled portion 42.

The mounting holes 50, 50′ may be placed in various positions of the protection bottom member 30. Accordingly, it is possible to adapt the protection member 6 to be attached to different excavators.

The protection member 6 is designed to be mounted on a swing boom of an excavator using the slots 34 and/or the holes 50.

FIG. 3B illustrates the protection member 6 of the rotation sensor assembly shown in FIG. 3A in an assembled configuration. It can be seen that the flange portions of the reinforcement member 38 extend between and bear against the protection top member 40 and the protection bottom member 30. Accordingly, the reinforcement member 38 supports the protection top member 40 and the protection bottom member 30.

FIG. 3C illustrates an exploded view of a protection member 6 of a rotation sensor assembly according to an embodiment. The protection member 6 corresponds to the one shown in and explained with reference to FIG. 3A.

FIG. 3D illustrates the protection member 6 of the rotation sensor assembly shown in FIG. 3C in an assembled configuration.

FIG. 4A illustrates an exploded view of a first portion 4 a rotation sensor assembly according to an embodiment. The first portion 4 is configured to be attached to the cap of an excavator. The first portion 4 comprises an L-shaped angle bracket 18 and a base bracket 10 having a foot portion 8 provided with two parallel and spaced apart feet. A plurality of slots 12 are provided in the upper portion of the base bracket 10. These slots 12 are configured to receive bolts 16 extending through the slots 12 for detachably attaching the base bracket 10 to a first part of the L-shaped angle bracket 18.

The shaped angle bracket 18 is equipped with a plurality of slots 12′ configured to receive bolts 16 extending through the slots 12 of the base bracket 10 and the slots 12′ of the angle bracket 18. A nut 14 is fixed to each bolt 16 to attach the base bracket 10 and the angle bracket 18 to each other in a firm and reliable manner. It may be advantageous that the slots 12 of the base bracket 10 extend perpendicular to the slots 12′ of the angle bracket 18 like shown in FIG. 4A.

The first portion 4 comprises a top bracket 20 configured to be detachably attached to the second part of the L-shaped angle bracket 18 by bolts 16 extending through the slots 12″ of the top bracket 20. Each bolt 16 is screwed into a threaded bore 11 provided in the top bracket 20, typically using a washer 15. A plurality of threaded bores 11 are distributed along the length of the top bracket 20. Accordingly, the second part of the L-shaped angle bracket 18 may be attached to different threaded holes 11 in order to achieve a desired degree of overlap between the second part of the L-shaped angle bracket 18 and the top bracket 20.

It may be advantageous that the threaded bores 11 are distributed along two parallel spaced apart lines extending along the length of the top bracket 20.

The first portion 4 comprises a sensor base 22 that is configured to be attached to the top bracket 20. The top bracket 20 is provided with threaded holes 11. The sensor base 22 is provided with through-going holes 9. Accordingly, the sensor base 22 can be attached to the top bracket 20 by inserting bolts 16 through the holes 9 of the sensor base 22 and screwing the bolts 16 into the threaded holes 11 of the top bracket 20.

The sensor base 22 comprises a socket 36 arranged and configured to be electrically connected to a cable provided with an electric plug. It may be advantageous that the socket 36 protrudes towards the distal end of the top bracket 20 or the base bracket 10.

The sensor base 22 is configured to receive and hereby provide an easy way of attaching the sensor portion to the sensor base 22 as shown in and explain with reference to FIG. 1A, FIG. 1B, FIG. 2A and FIG. 2B.

FIG. 4B illustrates the first portion 4 of the rotation sensor assembly shown in FIG. 4A in an assembled configuration.

FIG. 4C illustrates another view of the first portion 4 of the rotation sensor assembly shown in FIG. 4A in an assembled configuration.

FIG. 5A illustrates an exploded view of a protection member 6 of a rotation sensor assembly according to an embodiment. The protection member 6 comprises a protection bottom member 30 provided with a mounting portion 32 having two parallel spaced apart protruding sections each provided with a slot 34. The protection bottom member 30 comprises a planar portion and a bent portion 52 protruding perpendicular from the planar portion. It may be advantageous that the planar portion of the protection bottom member 30 is provided with a plurality of mounting holes.

The protection bottom member 30 comprises two female portions 44 each configured to receive a male portion (protruding member) 54 of the protection top member 40 of the protection member 6.

The bent portion 52 comprises threaded holes 58 each configured to receive a threaded portion of a bolt 16. The protection member 6 comprises a protection top member 40 having a L-shaped profile. The protection top member 40 comprises a planar portion and an angled portion 42 protruding from the planar portion. The angled portion 42 comprises two holes 56 each configured to receive the threaded portion of a bolt 16.

The protection member 6 comprises a reinforcement member 38 shaped as a U-shaped one-piece body provided with holes 46. The reinforcement member 38 is configured to be attached to the angled portion 42 by inserting bolts 16 through the holes 46 in the reinforcement member 38 and screwing the bolts 16 into the threaded holes 58 in the bent portion 52.

In an embodiment, the holes 46 have an elongated shape in order to ease the attachment of the reinforcement member 38 to the angled portion 42. The protection member 6 is designed to be mounted on a swing boom of an excavator using the slots 34 and/or the holes 50.

FIG. 5B illustrates the protection member 6 of the rotation sensor assembly shown in FIG. 5A in an assembled configuration. It can be seen that the flange portions of the reinforcement member 38 extend between and bear against the protection top member 40 and the protection bottom member 30. Accordingly, the reinforcement member 38 supports the protection top member 40 and the protection bottom member 30.

FIG. 6A illustrates a side view of an excavator according to an embodiment. FIG. 6B illustrates a perspective front view of the excavator shown in FIG. 6A. The excavator 60 comprises a cab 62 mounted on a base provided with a driving assembly 78. Accordingly, the excavator 60 is a tracked vehicle. In another embodiment, however, the excavator 60 may be wheeled. The excavator 60 comprises a mounting structure 80 rotatably mounted to the cab 62. The mounting structure 80 is mounted to a corresponding receiving structure of the cab 62 by a shaft 72. When the excavator 60 is arranged on a horizontal surface, as shown in FIG. 6A, the shaft 72 will be upright (extending vertically).

The excavator 60 comprises a boom 64 rotatably attached to the mounting structure 80 by a first boom joint 76. A first cylinder 68 is rotatably mounted to the mounting structure 80 by a first cylinder joint 74. The first boom joint 76 and the first cylinder joint 74 are spaced apart from each other. Thus, activation of the first cylinder 68 will cause the boom 64 to rotate about the first boom joint 76.

A stick 66 is rotatably attached to the distal end of the boom 64 by a second boom joint 76′. A second cylinder 68′ is rotatably attached to the boom 64 by a second cylinder joint 74′ and to the stick 66 by a third cylinder joint 74″. Thus, activation of the second cylinder 68′ will rotate the stick 66 about the second boom joint 76′ and thus the boom 64.

The excavator 60 comprises a bucket 70 rotatably attached to the distal end of the stick 66. A third cylinder 68″ is rotatably attached to the stick 66 and to the bucket 70. Accordingly, activation of the third cylinder 68″ will rotate the bucket 70 relative to the stick 66.

The mounting structure 80 is arranged to be rotated with respect to the longitudinal axis Z of the shaft 72. This may be done by applying a cylinder (not shown) rotatably attached to the cab 62 and to the mounting structure 80.

A rotation sensor assembly according to an embodiment may be attached to the excavator 60 to determine the rotational angle of the boom 64 with respect to the longitudinal axis X of the shaft 72.

FIG. 6B illustrates a perspective view of the excavator 60 shown in FIG. 6A. It can be seen that the mounting structure can rotate about the longitudinal axis Z of the shaft. The longitudinal axis B of the proximal portion of the boom 64 is indicated. The lateral axis X and longitudinal axis Y of the cab 62 are also indicated.

It can be seen that the rotational angle α of the boom 64 is approximately 90°. Accordingly, the boom 64 extends along the plane spanned by the longitudinal axis Y of the cab 62 and a vertical axis (an axis parallel to the longitudinal axis Z of the shaft. A rotation cylinder extends between the cab 62 and the mounting structure. The rotation cylinder is arranged and configured to rotate the mounting structure with respect to the shaft by which the mounting structure is rotatably attached to the cab 62.

FIG. 7A illustrates how the sensor components 22, 24 of a rotation sensor assembly according to an embodiment may be aligned. A sensor base 22 provided with a socket 36 is arranged above a magnetic sensor portion 24 of a rotation sensor assembly according to an embodiment.

In order to align the sensor base 22 and the sensor portion 24, two clamps 92 are inserted to clamp on both the sensor base 22 and the sensor portion 24. Each clamp 92 is inserted from opposing sides. Accordingly, the clamps 92 will guide the sensor base 22 and the sensor portion 24 into an aligned position. Once the sensor base 22 and the sensor portion 24 have been guided into an aligned position, the clamps 92 will maintain the sensor base 22 and the sensor portion 24 in the aligned position.

FIG. 7B illustrates the sensor components illustrated in FIG. 7A in an assembled configuration. In this configuration a cable tie 94 has been mounted and tied around the clamps to make sure the aligned position is maintained.

FIG. 8A illustrates how the sensor components 22, 24 of a rotation sensor assembly according to an embodiment can be aligned. A sensor base 22 provided with a socket 36 is arranged above a magnetic sensor portion 24 of a rotation sensor assembly according to an embodiment. Initially the sensor base 22 is arranged on the top of the sensor portion 24. Hereafter a single clamp 92 is inserted to clamp on both the sensor base 22 and the sensor portion 24. Accordingly, the clamp 92 will guide the sensor base 22 and the sensor portion 24 into an aligned position and maintain the sensor base 22 and the sensor portion 24 in the aligned position.

FIG. 8B illustrates a perspective top view of the sensor components 22, 24 illustrated in FIG. 8A in an assembled configuration mounted to a top bracket 20. The sensor components 22, 24 illustrated in FIG. 8A have been attached to the top bracket 20 by screwing bolts 7 into threaded holes of the sensor base 22. The bolts 7 extend through holes in the top bracket 20.

FIG. 8C illustrates a side view of the sensor components 20, 22, 24 illustrated in FIG. 8B. It can be seen that the clamp 92 maintains the sensor base 22 and the sensor portion 24 in the aligned position.

FIG. 9A illustrates a close-up view of the area of an excavator, in which a rotation sensor assembly according to an embodiment has to be mounted. The excavator comprises a stationary part referred to as the cab 62 and a boom 64 rotatably mounted to the cab 62. The boom 64 has a hydraulic hose 82.

FIG. 9B illustrates a close-up view of a fixation member 30 attached to the boom of the excavator shown in FIG. 9A. It can be seen that the fixation member 30 comprises a plate-shaped part provided with holes 34 arranged and configured to receive the bolts 86 of the boom 64. Accordingly, the fixation member 30 is configured to be fixed to the boom 64 using the bolts 86 of the boom 64.

FIG. 10A illustrates a first step of a method according to an embodiment. In this initial step, the fixation member 30 is fixed to the boom 64 using the bolts 86 of the boom 64. It can be seen that the fixation member 30 is provided with threaded holes 88 configured to receive bolts or threaded rods for attaching the sensor portion 24 to the fixation member 30. It is important to make sure that the fixation member 30 is centered to the platform of the boom. It is possible to use one or more spacers (e.g. washers) to close any gap between the boom and the fixation member 30.

FIG. 10B illustrates a second step of a method according to an embodiment. In this next step the sensor portion 24 (e.g. the rotation sensor magnet of the rotation sensor assembly) is attached to the fixation member 30. This may be done by screwing bolts into the threaded holes of the fixation member 30. The bolts are initially inserted through the through-bores of the sensor portion 24.

FIG. 10C illustrates a third step of a method according to an embodiment. In this step the first portion 4 is assembled. The relative position of the base bracket relative to the angle bracket is estimated by holding the sensor base on the center of the sensor portion. The bolts holding the sensor base and the sensor portion are not tightened yet. The rotation sensor assembly must be able to reach the center and should not hit the boom during rotation.

FIG. 10D illustrates a fourth step of a method according to an embodiment. In this step, the position of the first portion is checked. The bolts in the area 25 are not fastened yet because the relative position of the angle bracket and the top bracket should be adjustable in this stage. When the position of the first portion is correct, the bolts in the area 25 are fastened. Accordingly, the angle bracket and the top bracket can no longer slide relative to each other.

FIG. 10E illustrates a fifth step of a method according to an embodiment. In this step, the first portion is attached to the cab. This can be done using glue. After this step, in a sixth step, a protection member 6 is mounted as shown in FIG. 11A.

In FIG. 11A the angle α between foot portion 8 and base bracket 10 is indicated. Likewise, the angle β of the angle bracket 18 is indicated.

As indicated in FIG. 11B, the angle between the top bracket 20 and the base bracket 10 can be adjusted by inserting one or more spacers (e.g. a washer or a flat plate) 84 into the gap 90 between the base bracket 10 and the angle bracket 18.

LIST OF REFERENCE NUMERALS

• • 2 Rotation sensor assembly
  • 4 First portion
  • 6 Protection member
  • 7 Bolt
  • 8 Foot portion
  • 9 Hole
  • 10 Base bracket
  • 11 Threaded bore
  • 12, 12′ Slot
  • 12″, 12″ Slot
  • 14 Nut
  • 15 Washer
  • 16, 16′ Bolt
  • 18 Angle bracket
  • 20 Top bracket
  • 22 Sensor base
  • 24 Sensor portion
  • 25 Area
  • 26 Sensor mounting member
  • 28 Threaded rod
  • 30 Protection bottom member (intended for being mounted on a swing boom)
  • 32 Mounting portion
  • 34 Hole
  • 36 Socket
  • 38 Reinforcement member
  • 40 Protection top member
  • 42 Angled portion
  • 44 Female portion (opening)
  • 46 Hole
  • 50, 50′ Mounting hole
  • 52 Bent portion
  • 54 Male portion (protruding member)
  • 56 Hole
  • 58 Hole
  • 60 Excavator
  • 62 Cab
  • 64 Boom
  • 66 Stick
  • 68 Cylinder
  • 70 Bucket
  • 72 Shaft
  • 74 Cylinder joint
  • 76 Boom joint
  • 78 Driving assembly
  • 80 Mounting structure
  • 82 Hydraulic hose
  • 84 Spacer
  • 86 Bolt
  • 88 Threaded hole
  • 90 Gap
  • 92 Clamp
  • 94 Cable tie
  • Z Longitudinal axis
  • X Longitudinal axis
  • Y Longitudinal axis Y of the cab
  • B Longitudinal axis of the proximal portion of the boom
  • H Horizontal direction
  • α, β Angle