jack device equipped with a position sensor

Abstract

Title: Jack device with position sensor Jack device with position sensor, of the type comprising a tubular body (1), a rod (2) moved axially under the action of a fluid and which emerges from one end (13) of the body (1), while the other end (14) is equipped with a fixing eyelet (51), the body (1) incorporating a position sensor device (4), comprising a drum on which is wound a cable (41) the free end (42) of which is fixed 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) carrying the eyepiece (51), secured by screwing to the sleeve (3) by means of screws (50), the cover (5) being configured and the screws (50) being distributed to allow different positions of the cover (5) relative to the sleeve (3), and therefore several orientations of the eyepiece (51).Figure for the abridged version: Fig. 1.

Description

Title of the invention: 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 limited to, viticulture and agriculture, hydraulic, or even pneumatic, energy is primarily used via cylinders to move structures and tools. For certain operations, it is preferable, and even desirable, to be able to control the amplitude of the movements, and therefore the stroke of the various cylinders used.

[0003] Position sensor devices known as reel-type devices, intended for use with hydraulic cylinders, are already known. Such a device comprises a drum internally fixed to the base of the cylinder body, around which a cable is wound, the free end of which is fixed 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 displacement.

[0004] In practice, the sensor device must be integrated inside the body and secured to it. While it is possible to integrate the sensor device into the tube when the diameter is large, this is not the case when the diameter is small. In this case, it is necessary to construct the cylinder body in two parts: a tube to which a base containing the sensor device, or covering it, is attached at its end and secured to the tube. The base is secured to the tube by axial screwing, with the end of the tube and the base having suitable threads and tapped holes.

[0005] This solution, however, has a drawback. The base externally supports the eyelet for attaching the body, and screwing and tightening the base onto the end of the tube affects the orientation of the eyelet's axis. This orientation may then be incompatible with the position of the fluid supply connections and the passages of the rigid or flexible conduits connected to them. Furthermore, partial loosening is possible, resulting in a change in the orientation of the eyelet and therefore of the body.

[0006] To overcome this drawback, some propose to fix the orientation of the eyepiece, by immobilizing the base on the body by means of radially screwed set screws, however with the disadvantage of a risk of these screws coming loose, as well as play developing over time.

[0007] The present invention aims to provide a jack device with a sensor a position that addresses the various disadvantages mentioned above, while being simple and inexpensive in design.

[0008] The jack device with position sensor according to the invention is of the type comprising a tubular body radially provided with at least one fluid supply port, 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 directly or indirectly attached to said body, on which is wound a cable whose free end is attached to said rod, and whose unwinding is measurable, and it is characterized in that said body consists on the one hand of a tube extended, on the side opposite that from 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 attached to it by screwing,by means of screws whose screw 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 has a square cross-section, the cover is square in 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 has a round cross-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 become clearer from the following description, which relates to the attached drawing, which represents a non-limiting embodiment thereof.

[0015] In the attached drawing:

[0016] [Fig. 1] represents a schematic plan and exploded view of the jack device according to the invention.

[0017] [Fig.2]. represents a partial schematic view of the same jack device.

[0018] With reference to [Fig.1] we 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 tube-shaped body 1 delimiting a chamber 10, supplied with fluid by one or the other of two ports 11 and 12, a rod 2 arranged in chamber 10, the inner end of which is fitted with a piston 20 while its other end, external to body 1, is fitted with an eyelet 21. The spigot 11 is positioned near the end 13 of body 1 through which the rod is extracted while the spigot 12 is positioned near the other end 14.

[0020] According to the invention, the cylinder 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 disposed and fixed a position sensor device 4 of known type, comprising in a housing 40 a drum on which is wound a cable 41 the free end 42 of which 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 cylinder.

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

[0023] With reference to [Fig.2], one can see a non-limiting embodiment of the Cover 5. In this embodiment, there are eight screws 50, which are regularly spaced angularly. It will be understood that the cover 5 can be positioned in any direction relative to the hidden sleeve 3, and that consequently the orientation of the eyelet 51 relative to the ports 11 and 12 can be varied, as shown by the dashed lines.

Claims

Demands

1. A jack device with a position sensor, of the type comprising a tubular body (1) radially provided with at least one fluid supply port (11, 12), a rod (2) moved axially under the action of said fluid and emerging from one end (13) of said body (1), while the other end (14) is equipped with a mounting eyelet (51), said body (1) incorporating a position sensor device (4), comprising a drum directly or indirectly attached to said body (1), around which is wound a cable (41) the free end (42) of which is attached to said rod (2), and the unwinding of which is measurable, characterized in that said body (1) consists, on the one hand, of a tube (1) extended, on the side opposite to that (13) through which said rod (2) emerges, by a sleeve (3) welded to said tube (1), intended to house and immobilize said sensor device (4), and on the other hand, 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 screw 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).

2. 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.

3. Cylinder according to claim 1, characterized in that the sleeve (3) is of round section, and the cover (5) is attached to it by more than four screws (50) regularly spaced angularly.

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