Actuator device provided with a position sensor

Abstract

The invention relates to an actuator device with a position sensor, of the type comprising a tubular body (1), a rod (2) moved axially by a fluid and emerging from one end (13) of the body (1), while the other end (14) is provided with a fastening eye (51), wherein the body (1) incorporates a position sensor device (4), comprising a drum on which a cable (41) is wound, the free end (42) of which is rigidly attached to the rod (2), and the unwinding of which is measurable. The body (1) consists of a tube (1) extended by a sleeve (3) welded to the tube (1), housing the sensor device (4), and a cover (5) bearing the eye (51), rigidly attached by screwing onto the sleeve (3) by means of screws (50), wherein the cover (5) is configured and the screws (50) are arranged so as to allow different positions of the cover (5) with respect to the sleeve (3), and therefore a plurality of orientations of the eye (51).

Description

cylinder device equipped with a position sensor

[0001] The present invention relates to a jack device equipped with a position sensor.

[0002] In the field of machinery, particularly, but not exclusively, viticulture and agriculture, hydraulic or even pneumatic energy is mainly used, through cylinders, to set structures and tools in motion. For certain operations it is preferable, and even desirable, to be able to control the amplitude of movements, and therefore the stroke of the different cylinders used.

[0003] Position sensor devices known as reels are already known, intended to equip hydraulic cylinders. Such a device comprises a drum secured internally to the base of the cylinder body, on which is wound a cable whose free end is secured to the piston of the cylinder rod. When the rod moves, the cable rotates the drum while an electronic sensor converts the rotation into linear movement.

[0004] In practice, the sensor device must be integrated inside the body and secured there. While it is possible to integrate the sensor device into the tube when it has a large diameter, this is not the case when the diameter is reduced. In this case, it is necessary to construct the cylinder body in two parts, namely a tube to which is secured at the end a base comprising the sensor device or covering it, secured to the tube. The base is secured to the tube by axial screwing, the end of the tube and the base being provided with suitable threads and tappings.

[0005] This solution, however, has a drawback. In fact, the base externally carries the eyelet for fixing the body, and screwing and tightening the base onto the end of the tube affects the orientation of the axis of said eyelet, which may then be incompatible with the position of the fluid supply connections, and the passages of the rigid or flexible conduits connected to them. In addition, partial unscrewing is possible, resulting in a modification of the orientation of the eyelet and therefore of the body.

[0006] To overcome this drawback, some suggest fixing the orientation of the eyepiece, by immobilizing the base on the body using radially screwed point screws, with however the disadvantage of a risk of unscrewing these screws, as well as play over time.

[0007] The aim of the present invention is to propose a jack device with position sensor making it possible to overcome the various aforementioned drawbacks, while being of simple and inexpensive design.

[0008] The jack device with position sensor according to the invention is of the type comprising a tubular body provided radially with at least one fluid supply connection, a rod moved axially under the action of said fluid and which emerges from one end of said body, while the other end is equipped with a fixing eyelet, said body incorporating a position sensor device, comprising a drum secured directly or indirectly to said body, on which is wound a cable whose free end is secured to said rod, and whose payout is measurable, and it is characterized in that said body consists on the one hand of a tube extended, on the side opposite to that through which said rod emerges, of a sleeve welded to said tube, intended to house and immobilize said sensor device, and on the other hand of a cover which carries said eyelet, which closes said sleeve and which is secured to it by screwing,by means of screws whose screwing axes are parallel to that of said tube, said cover being configured and said screws being distributed so as to allow different positions of said cover relative to said sleeve, and therefore several orientations of said eyelet.,

[0009] According to a particular embodiment of the jack device according to the invention, the sleeve is of square section, the cover is of square shape and is fixed to said sleeve by means of at least four screws, one at each corner.

[0010] This configuration allows two different orientations of the eyepiece.

[0011] According to another particular embodiment of the jack device according to the invention, the sleeve is of round section, and the cover is secured to it by more than four screws regularly spaced angularly.

[0012] Such a configuration allows more than two orientations of the eyepiece.

[0013] Of course, the sleeve and its cover can have other shapes, and the number of screws can also vary.

[0014] The advantages and characteristics of the jack device according to the invention will emerge more clearly from the description which follows and which refers to the attached drawing, which represents a non-limiting embodiment thereof.

[0015] In the attached drawing:

[0016] represents a schematic plan and exploded view of the jack device according to the invention.

[0017] . represents a partial schematic view of the same jack device.

[0018] With reference to the one can see a jack device according to the invention, in this case a double-acting jack.

[0019] It comprises, in a manner known per se, a body 1 in the form of a tube delimiting a chamber 10, supplied with fluid by one or other of two tappings 11 and 12, a rod 2 arranged in the chamber 10, the end of which internal to the body 1 is provided with a piston 20 while its other end, external to the body 1, is provided with an eyelet 21. The tapping 11 is positioned close to the end 13 of the body 1 through which the rod is extracted while the tapping 12 is positioned close to the other end 14.

[0020] According to the invention, the jack further comprises a sleeve 3, secured by a weld S to the body 1 in the extension thereof at its end 14. The sleeve 3, delimits a cavity 30 in which is arranged and fixed a position sensor device 4 of known type, comprising in a housing 40 a drum on which is wound a cable 41 whose free end 42 is fixed to the piston 20. The unwinding of the cable 41 makes it possible to measure the stroke of the rod 2.

[0021] The sleeve 3 is closed with a cover 5 by means of screws 50, which pass through the cover 5 and are screwed into the sleeve 3, along axes V parallel to the axis XX' of the jack.

[0022] The cover 5 has an eyelet 51, that of the attachment of the body 1.

[0023] With reference to the, one can see a non-limiting embodiment of the cover 5. In this embodiment, the screws 50 are eight in number, and are regularly angularly spaced. It will be understood that the cover 5 can be positioned indifferently with respect to the sleeve 3 which is not visible, and that consequently the orientation of the eyelet 51 can be varied with respect to the tappings 11 and 12, as shown in broken lines.

Claims

Cylinder device with position sensor, of the type comprising a tubular body (1) provided radially with at least one fluid supply connection (11, 12), a rod (2) moved axially under the action of said fluid and which emerges from one end (13) of said body (1), while the other end (14) is equipped with a fixing eyelet (51), said body (1) incorporating a position sensor device (4), comprising a drum secured directly or indirectly to said body (1), on which is wound a cable (41) whose free end (42) is secured to said rod (2), and whose payout is measurable, characterized in that said body (1) consists on the one hand of a tube (1) extended, on the side opposite that (13) through which said rod (2) emerges, of a sleeve (3) welded to said tube (1), intended to house and immobilize said sensor device (4), and on the other hand of a cover (5) which carries said eyelet (51),which closes said sleeve (3) and which is secured to it by screwing, by means of screws (50) whose screwing axes (V) are parallel to that (XX') of said tube (1), said cover (5) being configured and said screws (50) being distributed so as to allow different positions of said cover (5) relative to said sleeve (3), and therefore several orientations of said eyelet (51)., Cylinder according to claim 1, characterized in that the sleeve (3) is of square section, the cover (5) is of square shape and is fixed to said sleeve (3) by means of at least four screws (50), one at each corner. Cylinder according to claim 1, characterized in that the sleeve (3) is of round section, and the cover (5) is secured to it by more than four screws (50) regularly spaced angularly.

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