APPARATUS FOR CATCHING AN OBJECT

Abstract: A catching apparatus having a body (4) to which a cylindrecal tube (1) open at both ends thereof, inflatable when supplied with a fluid such as air is fixed at both ends thereof as sealed, whereby a fluid-filled object (11) is caught by the surface of the tube (1) inflated as a fluid is supplied into a sealed space (A) defined between the tube and the body. Also an inflation limiting member (6) is provided in a part of an area in which the tube inflates to limit the inflation of the tube to within a desired range.

Description: BACKGROUND OF THE INVENTION Field of the Invention: The present invention is related to apparatus for catching objects particularly objects with a short portion to be caught, for instance blood filters for dialysis, comprising an inflatable cylindrical tube of elastic material and open at both ends for gripping the object, said tube being fixed on a cylindrical body and inflatable when supplied with a fluid such as air. Description of the prior Art: The prior art is described in the following by Figures 1 to 5 of the drawings showing in: Fig. 1 a sectional view explaining the use of a typical conventional catching apparatus; Fig. 2 a schematic drawing of a dryer for blood filters for artificial dialysis; Fig. 3 the front view showing the catching of the filters shown in Fig. 2 by the conventional catching apparatus; Fig. 4 and 5 sectional views, respectively, explaining the drawbacks of the conventional catching apparatus. A typical conventional catching apparatus shown in Fig. 1 comprises a hollow cylindrical body 100, a flange 101 formed on the outer circumference of the body 100, an air passage 102 formed in the body and flange 101, a cylindrical tube 1 open at the both ends thereof, inflatable when air is supplied and of which both ends are secured as sealed with calking rings 2 and 3 respectively, to the body 100, a container 103 which is fixed as sealed to the flange 101. When a liquid L is supplied into an object 10 to be caught by this apparatus for the purpose of washing, the surface of contact between the tube 1 and the object 10 has to be sealed as the case may be. Assume in this case that the pressure of the air A to be supplied into the tube 1 is P A and the pressure of the liquid L is P L . When the pressures are so ajusted that P A is smaller than P L , the liquid L in the container 103 will not leak out. The object 10 shown in Fig. 1 has a sufficiently long portion thereof which is to be caught by the tube 1; however, in case of an object of which such portion is short, for example, in case blood filters 200 for artificial dialysis are held by a multi head catching apparatus inside a dryer as shown in Figs. 2 and 3, the air supply tubes 200A are so short in some cases that when the dry air A₁ is supplied into the filters 200, the air leaks out. If the pressure of the air A to be supplied into the tube 1 is raised for the purpose of preventing such air leak as well as for secure catching of the object 11, the tube 1 will close the opening of the object 11 as shown in Fig. 4, causing it impossible to supply the liquid L ( or the dry air A₁) into the object 11. On the contrary, if the pressure of the air A is reduced, the sealing becomes poor as shown in Fig. 5, resulting in leak-out of the liquid L. Note that even in case it is not necessary to supply the liquid L into the object, if the portion of the object to be caught by the catching apparatus is smaller than the tube, the object cannot positively be caught. It is further known by EP 0 259 518 A2 a device for repairing underground savage system pipes, said device consisting of a cylindrical shaped so-called "packer" inflatable by compressed air and having in it conduits for the feeding of sealing material for the repair of holes, ruptures and tears in said pipes. This packer is consisting of a tube of an elastic material e.g. rubber, the open ends of which are closed by non-elastic end-discs. The essential feature of this tube is, that its middle section is stiffer than the sections on both ends such that inflated said end sections will become more extended than the middle section which forms together with the inner wall of the pipe to be repaired a space in which the paste-like repairing material is to be exhausted. Such a packer is however neither specified nor qualified for catching small objects with a short portion to be caught. If an elastic closed tube has been made stiffer in its middle portion than on its end portions, for instance by a second rubber layer in said middle portion firmly connected with said tube and such a tube is inflated it will not form a distinct zone of enlarging-limitation as the object of the invention requires. SUMMARY OF THE INVENTION Accordingly, the present invention seeks to provide an apparatus for catching an object or the like, which can positively catch even an object of which the portion to be caught by the catching apparatus is smaller than the tube, can securely catch even an ovject which is being supplied with a fluid, and also can securely hold an object with a part of the inflated tube surface. To this end, the catching apparatus according to the present invention has provided in a part of an area in which the tube inflates an inflation limiting member which limits the inflation of the tube to within a desired range. According to the present invention, the inflation limiting member is so provided as to be within a part of the area in which the tube inflates, so that when the fluid is supplied into the tube under such a pressure as provides a sealing between the tube and an object to be caught, there is a good sealing between the inflated tube surface in contact with the object while the latter and the tube inflated surface not in contact with the object is limited by the inflation limiting member from being inflated more than predetermined, whereby the object can be more securely caught by the tube and better sealed. These and other objects and advantages of the present invention will be better understood from the ensuing description made, by way of example, of the embodiments of the present invention with reference to the drawings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Fig. 6 is a sectional view of a first embodiment of the present invention; Fig. 7 is a sectional view showing an example use of the first embodiment; Fig. 8 (a) is a second embodiment of the present invention; Fig. 8 (b) is a sectional view, partially enlarged in scale, of the second embodiment; Fig. 9 is a sectional view of a third embodiment of the present invention, showing when it is in used position; Fig. 10 is a sectional view of a fourth embodiment of the present invention, showing when it is in used position; Fig. 11 is a sectional view of a fifth embodiment of the present invention, showing when it is in used position; Fig. 12 (a) and (b) are sectional views, respectively, of a sixth embodiment of the present invention; Fig. 13 is a sectional view to explain the supply of fluid in the sixth embodiment; Fig. 14 is a sectional view of a seventh embodiment of the present invention; Fig. 15 is a sectional view of an eighth embodiment of the present invention; Fig. 16 is a sectional view of a ninth embodiment of the present invention; Fig. 17 is a sectional view of a tenth embodiment of the present invention; Fig. 18 is a sectional view of a eleventh embodiment of the present invention; Fig. 19 is a sectional view of an object suitable for catching by the catching apparatus according to the eleventh embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the first embodiment shown in Fig. 6, the catching apparatus has a body 4 to which a cylindrical tube 1 open at both ends thereof is so fixed at both ends thereof that the inflation surface of the tube 1 is inside the body 1. The body 4 has formed therein a passage 5 to supply a fluid A such as air into the tube 1. The tube 1 is fixed at both ends thereof to the body 5 with calking rings 2 and 3. The passage 5 is formed also in a flange portion 4A of the body 4, and there is secured to the flange portion 4A an inflation limiting member 6 which limits the inflation of the tube 1. Fig. 7 shows the catching apparatus according to the first embodiment which is catching an object 11. The inside diameter of this object 11 is nearly the same as the inside diameter of the inflation limiting member 6. Since, the object 11 has a flange 11A, the portion thereof which can be caught by the tube 1 is extremely short. The flange portion 4A of the catching apparatus shown in Fig. 6 is so fixed to a container 7 as sealed that a fluid B such as a liquid, dry air or the like flowing into the container is supplied into the object 11. The clearance Δt between the upper end of the inflation limiting member 6 and the lower end of the object 11 is preferably zero, but these ends may have a slight clearance between them. As shown in Fig. 7, when the object 11 is caught by the tube 1, the fluid A is supplied into the tube 1 under a predetermined pressure so as to ensure an ample sealing between the tube 1 and object 11. At this time, the existence of the inflation limiting member 6 permits to prevent the inflated surface of the tube 1 not in contact with the object 11 from closing the passage to the object 11, whereby the fluid B can be supplied into the object 11. Fig. 8 (a) and (b) show the second embodiment according to which the inflation limiting member 6 is provided easily removable from the flange portion 4A of the body 4, and the inflation limiting member 6 has a bulged end 6A which is to be press-fitted into a counterpart concavity 4B formed in the flange portion 4A. According to the third embodiment shown in Fig. 9, the inflation limiting member 6 is secured to the container 7 and holes 6B are formed at several places in the inflation limiting member 6 to pass the fluid B. Fig. 10 shows the fifth embodiment according to which the inflation limiting member 6 is secured to the container 7 as in the fourth embodiment but in a different position. Also according to the fifth embodiment shown in Fig. 11, the inflation limiting member 6 is secured to the container 7 in another different place. In all the above-mentioned embodiments, the tube 1 is inflated inwardly and the fluid B is supplied into the object. In the sixth embodiment shown in Figs. 12 (a) and (b), the inflation limiting member 6 is simply inserted into the tube 1, which is different from the above-mentioned embodiments in which the inflation limiting member 6 is secured to the flange portion 4A of the body 4 or to the container 7. According to the sixth embodiment, a pipe is used as the inflation limiting member 6 and the outside diameter of the pipe is selected to be slightly larger than the inside diameter of the tube 1 not yet supplied with the fluid A, so that the pipe inserted once in the tube 1 will not come off. In this catching apparatus, when the tube 1 is inflated as supplied with the fluid A, the pipe being the inflation limiting member 6 is moved downward a distance as shown in Fig. 12 (b). Hence, the upper portion of the tube 1 which is not limited in motion by the pipe becomes free from any slack and is inflated circularly to securely catch the object. The pipe being the inflation limiting member 6 is moved downward when the fluid A is supplied for the following reason: Assume the following as shown in Fig. 13: d₁ : minimum diameter of tube 1 d₂ : effective diameter of upper portion of tube 1 d₃ : effective diameter of lower portion of tube 1 These factors have the following relation among them: d₁ < d₂ < d₃ Assume that the forces action on the upper and lower portions of the tube 1 are F U and F D . These parameters F U and F D can be expressed as follows: Therefore, F D > F U According to the seventh embodiment shown in Fig. 14, the inflation limiting member 6 is provided with a flange 6C. In the eighth embodiment shown in Fig. 15, the container 7 has formed therein an air passage 13 for preventing the tube 1 from being difficult to inflate as the pressure of the fluid B rises. Also the ninth embodiment shown in Fig. 16 has a similar function. In this embodiment, when the inflation limiting member is moved downward, an elastic member 14 adheres to the inner bottom of the container 7 to prevent the fluid B from going into an external air passage. According to the tenth embodiment shown in Fig. 17, the inflation limiting member 6 has formed thereon a hose fitting 60 to which a hose 15 for supplying the fluid B is to be connected as fitted. In the eleventh embodiment shown in Fig. 18, the inflation limiting member 6 is divided in two parts, which are provided on the top and bottom, respectively, of the tube 1 so that the central portion of the tube 1 is more inflated than the rest thereof. This catching apparatus is suitable for use to catch an object 20 shown in Fig. 19.

Claims: Apparatus for catching objects (11), particularly objects with a short portion to be caught, for instance blood filters for dialysis, comprising an inflatable tube (1) for gripping the object and an inflation limiting member (6) for limiting inflation of said tube, wherein the inflatable tube (1) is mounted on a hollow cylindrical body (4) having opposed open ends, said tube having open ends and being adapted to be inflatable inwardly with respect to said body (4) when supplied with a fluid to form an inflated surface, said open ends being folded outwardly over respective opposite ends of said body (4) and affixed to the radially outer surface of it, whereby a sealed space is defined between said body (4) and said tube (1), the tube (1) having inflated and uninflated states and the inflation limiting member (6) being inserted axially partially into the tube (1). Apparatus according to claim 1, wherein the inflation limiting member (6) has an outside diameter slightly larger than the inside diameter of the tube (1) in its uninflated state.

Inventors: FUKUYAMA, HIROSHI, SATO, NAOMI, WATANABE, ISAO
Applicants: BRIDGESTONE CORPORATION
Application year: 1989
Main classification: F16L37
IPC codes: F16L37, B23P19, B25J15