FR2845364A1 - Cereal grain sampling unit telescopic arm has square tubes with sealed sliding joint and piston actuator - Google Patents

Abstract

A cereal grain sampling unit telescopic arm (2) has a square central tube (2a) with one end fixed to a support and internal tube (2b )with sampling probe and piston actuator (16) to drive the cover (2c) and internal tubes which are fixed together by a sliding joint (9) comprising half shells with seals.

Description

The invention relates to a telescopic arm for a device for

  pneumatic removal of granular or powdery materials, more particularly intended

  to the taking of cereal samples.

  It is common to take grain samples by means of probes articulated at the end of at least one support arm, itself articulated on a support generally in the form of a mast.

  The probes intended to immerse in the product to be sampled are tubular and are generally connected in their upper part to a flexible pipe which is connected

  on a product suction and recovery device.

  The flexible suction and recovery hose in this case generally runs along the support arm of the probe, before being connected to the suction device. For technical reasons, the probe is articulated on the arm, so that

  be able to allow the probe to remain in a vertical position during its descent into the product.

  In addition, this articulation, with cardan joint for example, is also essential for safety reasons in the event of an impact on an obstacle and in particular against the bucket in which the product to be taken is located (

  premature advancement of said bucket during removal).

  The flexible suction hose which is connected to the probe is obviously a handicap, due to its exposure to the open air, its unsightly appearance and the discomfort it gives at the level of the articulation of the probe and this is why we have already imagined, as described in the French patent published under the number 2,597,953, a tubular support arm connected to the probe, in such a way that the product to be sampled passes directly from the probe into said arm, the aforementioned invention further solving the delicate problem of the articulated suspension of the probe, so that the product can

  pass tightly through said joint.

  In such a device, the length of the arm is fixed and determined, which limits

of course its area of action.

  This is in particular why the French patent published under the number 2 633 487 proposes an interesting device, with double rotation, called "gyroscopic"

  allowing to increase the access surfaces of the probe.

  Such a device is very satisfactory above completely open skips, which is not always the case, for example when it is a question of taking samples from wagons or tank trucks whose openings are necessarily limited. , hence the difficulty in positioning the right probe

  above the sampling area.

  To improve these devices, we then thought of designing a telescopic arm. However, if already without passage of product inside the arm the problem to be solved is difficult due, inter alia, to the presence of the suction pipe and guiding difficulties, the passage through the arm of the product sucked in as described above

  also requires sealing.

  It is precisely the object of the invention to solve these problems by proposing an arm for a pneumatic device for collecting granular or powdery materials, articulated at one end to a support and whose other end carries a sampling probe, said arm and said probe being tubular for the passage of the product to be sampled, an arm which is remarkable in that it comprises a central tube 15 one end of which is articulated to the support, an inner tube mounted in a sliding and telescopic manner by the free end of the central tube and the end of which leaves said central tube is connected to the sampling probe, and a covering tube which is integral with the inner tube and which is slidably mounted on the central tube so as to permanently cover the part of an inner tube which extends out of the central tube during its sliding, while an actuating means is provided for entering moving the covering tube and the inner tube which slide respectively on and in the central tube.

  The solution according to the invention therefore consists in producing a sealed telescopic arm 25.

  According to one embodiment, the central, interior and covering tubes respectively have a square section while the covering tube and the tube

  inside are made integral with each other by their ends facing the probe.

  For example, the tight sliding of the covering tube on the central tube is ensured by a system comprising at least one sliding joint disposed in a sleeve fixed to the end of the covering tube opposite to that by which it is fixed to the inner tube. while the sleeve further comprises at least one shoe

slip.

  Advantageously in this case, the sleeve consists of two half-shells in which are housed the seal (s) and the sliding pad (s).

  According to one embodiment, the means for actuating the inner and covering tubes comprises a jack whose end of the rod is fixed to said covering tube.

  The invention will be clearly understood on reading the description which follows and

  which refers to the accompanying drawings in which: - Figures 1 and 2 show an automatic withdrawal device provided with an arm according to the invention, in low positions, respectively with retracted arm and extended arm, - Figure 3 shows a a little more in detail the arm of the device of FIGS. 15 1 and 2, FIG. 4 is a section on IV- IV of FIG. 3,

  - Figure 5 is an exploded view of the arm of Figures 1 to 4.

  The sampling device shown by way of example consists of a

  support 1 in the form of a mast on which is articulated in rotation and in elevation an arm 2 at the end of which is suspended a sampling probe 3 (FIGS. 1 and 2).

  The arm 2 is tubular to allow the passage of the granular or pulverulent product sampled, from the probe 3 to a place of storage, transport, or other, by an evacuation pipe 4 provided towards the end of the articulated arm 2 on the mast 1, while the probe 3 is here also suspended from said arm 2 by means of a

  joint 5 which also allows the product to pass, such as a hollow ball joint.

  The arm 2 consists of a central tube 2a (here of square section), which is fixed by one end to a frame 6 articulated and motorized on the mast 1 (FIGS. 1 to

  3) and which connected by this end to the evacuation pipe 4.

  In the central tube 2a is slidably mounted telescopically an inner tube 2b (Figures 3, 4, 5) which opens in the central tube 2a and which is provided at its end with a butt 7 intended to be connected to the hinge 5 of probe 3

(Figures 1, 2 and 5).

  On the central tube 2a is slidably mounted a covering tube 2c, one of the ends of which is fixed for example by a nozzle 8 (Figures 1, 2 and 5), on the end provided with the stock 7, of the inner tube 2b . The three tubes 2a, 2b and 2c are therefore coaxial and the fact that the covering tube 2c is integral with the inner tube 2b, it is understood that these two tubes slide respectively on and in the central tube 2a, the diameters of the tubes being

  obviously chosen accordingly to allow said sliding.

  In order to allow suction by the tubes 2b and 2c towards the pipe 4, it is of course necessary to ensure a seal between the sliding tubes 2a and 2b and it is

  precisely the function of the covering tube 2c.

  The joining of the ends of the tubes 2a and 2c by means of the end-piece 8,

  allows a perfect seal at this junction and it is understood that the difficulty lies at the free end of the tube 2c.

  To ensure good sliding of the covering tube 2c on the central tube 2a, and this in a sealed manner, the invention proposes to arrange this

  end of a sliding and sealing system 9.

  The system 9 shown and seen in more detail in FIGS. 4 and 5, comprises a sleeve formed by two half-shells 1 a, 1Ob of U-section as shown

indeed said Figures 4 and 5.

  The half-shells 10a, 10b are fixed to the tube 2c by means, for example, of an end flange II of the tube 2c and of corresponding half-flanges provided on the half-shells 10a, 1Ob, while l 'other side, the half-shells 25 are partly closed by a plate 12 perforated in its center, while between the flange 11 of the tube 2c and the half-shells and between the latter and the plate 12, are

  further provided here seals 13a, 13b.

  The seals 13a and 13b are in particular provided for ensuring the maintenance of two felt seals 14a, 14b of U-shaped section intended to be clamped between the half-shells 10a, 10b and the covering tube 2c on which they can slide, the

  seals 13a, 13b thus further ensuring additional sealing.

  Preferably, the invention provides in addition to also enclose between suitable flanges of the two half-shells 10a, 10b, two guides or sliding pads 15a, 15b which come into contact with the covering tube 2c as the

clearly shows figure 4.

  In this way, the assembly 9 ensures good sealing and good guidance in

  translation of the tube 2c on the tube 2a and of the tube 2b in the tube 2a.

  It is understood that the tube 2c partially covers the tube 2a, but of course it covers the inner tube 2b over its entire length which projects from the tube 2a during

its sliding.

  In order to ensure the motorization of the sliding of the tubes 2b and 2c, the inventor has provided an actuating means in the form here of an actuator 16, for example electric i0, which is fixed for example on an axis 17 (figure 3) and whose end of the

  rod is fixed to a yoke 18 of the covering tube 2c.

  The jack 16 thus makes it possible to telescopically extend or retract the arm 2 by sliding the tubes 2c and 2a relative to the central tube 2a, as explained above.

Claims (6)

  1) arm (2) for a pneumatic sampling device for granular or powdery materials, articulated at one end to a support (1) and the other end of which carries a sampling probe (3), said arm and said probe being tubular for the passage of the product to be sampled, characterized in that it comprises a central tube (2a), one end of which is articulated to the support (1), an internal tube (2b) mounted in a sliding and telescopic manner by the free end of the tube central (2a) and the end of which leaves said central tube is connected to the sampling probe (3), 10 and a covering tube (2c) which is integral with the inner tube (2b) and which is   slidably mounted on the central tube (2a) so as to permanently cover the inner tube part (2b) which extends outside the central tube (2a) during its sliding, while an actuating means ( 16) is provided for moving the covering tube (2c) and the inner tube (2b) which move respectively on and in the central tube (2a).   2) Arm according to claim 1, characterized in that the respectively central (2a), inner (2b) and covering (2c) tubes have a square section.   3) arm according to one of claims 1 and 2, characterized in that the covering tube (2c) and the inner tube (2b) are made integral with one another by their   ends facing the probe (3).   4) arm according to one of claims 1 to 3, characterized in that the   sealed sliding of the covering tube (2c) on the central tube is ensured by a system (9) comprising at least one sliding joint (14a, 14b) disposed in a sleeve (10a, 10b) fixed to the end of the tube overlap (2c) opposite to that   by which it is fixed to the inner tube (2b).   ) Arm according to claim 4, characterized in that the sleeve comprises   furthermore at least one sliding pad (15a, 15b).   6) Arm according to one of claims 4 and 5, characterized in that the sleeve consists of two half-shells (10a, 10b) in which are housed the   or the seals (14a, 14b) sealing and the sliding pad (s) (15a, 15b).   7) arm according to one of claims 1 to 6, characterized in that the means   actuating the inner tubes (2b) and covering (2c) comprises a cylinder   (16) whose end of the rod is fixed to said covering tube (2c).