FR2811724A1 - Position sensor fixing rail for a pneumatic or hydraulic jack piston uses a screw operated pivot to lock sensor into a fixing rail slot forming part of the body of the jack - Google Patents

Abstract

The sensor (1) has an upper surface which when mounted in a slot (4) of a fixing rail (3) is flush with it so as to protect against knocks. A plate (8) positioned in the slot holds the sensor supply cable in the base of the slot. The rail (3) is fixed on the body of the jack and forms an integral part of it. Sensor fixing comprising a rail (3) mounted on the external surface of the body of the jack and along its axis. The rail has a slot (4) with a section designed to receive the sensor. The sensor includes a pivot (5) fixed by a screw (6) or similar. The pivot occupies two positions produced by rotation of the screw. In a first position the pivot is flush with the lateral walls of the sensor so as to allow the mounting of the sensor from the top of the slot. In a second position, the pivot projects from the lateral walls of the sensor so as to lodge itself in the bottom of the slot and lock the sensor without subjecting it to any compression force.

Description

The present invention relates to a device for mounting a

positioning detector

  pneumatic or hydraulic cylinder piston on the body of the latter.

  In known manner, a position detector, such as a magnetic proximity detector, is installed on the body of a pneumatic or hydraulic cylinder in order to detect the

position of the piston of this jack.

  In one of the known mounting arrangements of such a detector, a support rail comprising a groove is mounted axially on the body of the jack, between its two ends. Another device is also known in which the groove is directly integrated on the body of the jack. The detector is then placed in this groove and is held in position by means of fixing members.

appropriate (screw type, etc.).

  Such configurations have the advantage of being able to adjust the position of the detector along the groove, in the axial direction of the cylinder body, which makes it possible to choose the position of the piston which it is desired to detect. However, when it is necessary to dismantle the detector thus disposed in the groove in order to carry out, for example maintenance operations, such an installation has the drawback of having to carry out complete disassembly of the jack or any mechanical device

incorporating the latter.

  In particular, when it is a rail mounted on the cylinder body, the detector is conventionally inserted into the support rail by one of the ends of the latter, and it is therefore necessary to dismantle it before being able to

remove said detector.

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  It will be readily understood that this disassembly operation has a superfluous nature, in particular when the jack or the device integrating the latter is

difficult to access.

  Furthermore, the particular shape of such detectors is generally such that, when mounted in their groove, they protrude with respect to this support so that these detectors have a large surface area for possible shocks which could risk disrupting them, or even

to damage them.

  The present invention aims to overcome such drawbacks by proposing a device for mounting a position detector of a piston of a pneumatic or hydraulic cylinder on the body of said cylinder which allows very easy disassembly of the detector, without having to disassemble the cylinder. in whole, and whose particular shape allows said detector not to be protruding

in relation to its support.

  To this end, the mounting device according to the invention of a detector making it possible to detect the position of a pneumatic or hydraulic jack piston on the body of said jack, said device comprising a rail mounted on the external surface of said body and arranged along its axis, said rail comprising a groove whose cross section in the form of a dovetail is capable of receiving said detector, said device being characterized in that the detector comprises at least one pivot secured to a screw or the like, said pivot able to occupy two positions obtained by rotation of said screw or the like: - in a first position, this is flush with the side walls of said detector so as to allow mounting of said detector by the top of the groove;

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  - In a second position, it projects relative to the side walls of said detector so as to be housed in the bottom of said groove, in order to mechanically block said detector without generating any compressive force thereon. Other features and advantages of this

  invention will emerge from the description given below, in

  reference to the accompanying drawings which illustrate an embodiment thereof devoid of any limiting character. In the figures: - Figure 1 is a perspective view of the device according to the invention according to a first embodiment; - Figure 2 is a perspective and exploded view of the device according to a second embodiment; - Figure 3 is a perspective and exploded view of the detector device according to the invention; - Figure 4 is a bottom view of Figure 3; - Figure 5 is a sectional view along V-V of the

figure 1.

  If we refer to Figure 1 which shows a preferred embodiment of the device according to the invention, we see that it consists of a detector 1 mounted on a body 2 of a pneumatic or hydraulic cylinder. A piston (not shown) is installed inside the body 2

  of said cylinder so as to move there from front to back.

  When compressed air or pressurized liquid enters or is expelled from the pair of chambers separated by the piston, the latter moves back and forth in the cylinder body. In addition, an annular magnet which is detected by the detector 1 is mounted on the external surface

piston.

  According to a preferred embodiment of the detector 1, this is in the form of a magnetic proximity detector which delivers a signal when a magnet (the detected object) approaches it. Of course, the object detected and the detector are not limited to a magnet and a magnetic proximity detector. For example, the detected object can be made of metal and the detector can be a high-frequency detector which detects an induced signal and transforms it into an output signal. The detector mounting device 1 according to the invention consists of a detector 1 and a rail 3 thanks

  to which said detector is installed on the body 2 of the pneumatic or hydraulic cylinder.

  According to an advantageous characteristic of the invention, this rail 3 is either brought to the body 2 of the jack using appropriate fixing members (cf. FIG. 1), or it is an integral part of the external surface of said body

cylinder (see Figure 2).

  According to an essential characteristic of the invention, the rail 3 has a groove 4 whose cross section in the form of a dovetail is capable of receiving the detector 1

(cf. figure 5).

  The detector 1 is then mounted on top of the said rail, in the groove 4 fitted on the latter, which avoids having to dismantle the latter during installation.

or removal of said detector.

  To do this, there is installed on the detector 1 at least one pivot 5 secured to a screw 6 or the like. This pivot is positioned in a slot 7 fitted on said detector and can occupy two positions which are obtained by simple rotation of the screw 6 or the like: - in a first position, the pivot 5 is flush with the side walls of said detector so as to allow mounting the detector 1 from above the groove 4; - In a second position (cf. FIG. 4), it projects relative to the side walls of said detector so as to be housed in the bottom of the groove 4, in order to mechanically block the detector 1 without generating

  compression force thereon.

  In order to pass from one position of the pivot 5 to the other, a simple rotation of the screw 6 is sufficient. This rotation can be performed for example using a standard screwdriver. Firstly, the pivot 5 is positioned so that it is flush with the side walls of said detector. This is then inserted into the groove 4 from above it, and a simple rotation of the screw 6 secured to the pivot 5 allows

  hold the detector 1 in place in said groove.

  Indeed, this rotation of the screw 6 or the like has the effect of positioning the pivot 5 so that it protrudes relative to the side walls of the detector 1. The pivot is then inserted into the bottom of the groove 4 in the shape of a dovetail, rises slightly under the effect of rotation of said screw, and thus comes to lock said detector in position without generating any force

  compression on it (see Figure 5).

  Furthermore, the detector 1 can slide in the groove 4 in order to choose the position of the piston which it is desired to detect. To do this, a rotation of the screw 6 or the like then makes it possible to reposition the pivot 5 in the lumen 7 so as to allow the movement of the detector

along the body 2 of the jack.

  The presence of this pivot projecting laterally at the bottom of the dovetail-shaped groove thus increases the mechanical stability of the assembly and allows the detector to be used in delicate applications such as in a vibratory environment, in applications subject to shocks or variations in

temperature, etc ...

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  Of course, a plurality of rails 3 can be installed at different positions on the external surface of the body 2 of the jack so as to receive one or more

  piston position detectors of said cylinder.

  According to another advantageous characteristic of the invention, the detector 1 has an upper surface such that, when said detector is mounted in the groove 4, this surface is flush with the rail 3. Thus, the detector does not protrude relative to the groove 4 in the shape of a dovetail which makes it possible to protect it from possible shocks and improper handling which may

disturb or even damage it.

  According to yet another advantageous characteristic of the invention, the device comprises a plate 8 able to be positioned in the groove 4 so as to hold in position a power cable 9 of the detector 1 in the bottom of said groove. This plate 8, associated with the particular shape of the detector 1, thus makes it possible to avoid any involuntary disruption of the position of the detector, the assembly being perfectly integrated inside the

groove 4.

  The present invention as described above offers multiple advantages; in particular, it offers a device for mounting a detector which is easy to use and which allows the detector to be set up and removed without having to dismantle the jack or any mechanical device.

incorporating the latter.

  It remains to be understood that the present invention is not limited to the exemplary embodiments described and shown above, but that it encompasses all variants thereof.

Claims (4)

  1 - Device for mounting a detector (1) for detecting the position of a pneumatic or hydraulic cylinder piston on the body (2) of said cylinder, said device comprising a rail (3) mounted on the external surface of said body and arranged along its axis, said rail comprising a groove (4) whose cross section in the form of a dovetail is capable of receiving said detector, said device being characterized in that the detector comprises at least one pivot (5) integral a screw (6) or the like, said pivot being able to occupy two positions obtained by rotation of said screw or the like: - in a first position, this is flush with the side walls of said detector so as to allow said detector to be mounted by the top of the groove; - In a second position, it projects relative to the side walls of said detector so as to be housed in the bottom of said groove, in order to mechanically block said detector without generating any force compression on it.   2 - Device according to claim 1, characterized in that the detector (1) has an upper surface such that, when said detector is mounted in the groove (4), this surface is flush with the rail (3)   in order to protect said detector from possible shocks.   3 - Device according to one of claims 1 or 2,   characterized in that it comprises a plate (8) positioned in the groove (4) so as to hold in position a supply cable (9) of the detector (1) in the bottom of said groove.   4 - Device according to any one of   previous claims, characterized in that the rail   (3) is brought to the body (2) of said cylinder. 8 2811724   - Device according to any one of   Claims 1 to 3, characterized in that the rail (3)   is an integral part of the outer surface of the body (2) of said cylinder.