EP1260249B1 - Exercise apparatus with pneumatic cylinder - Google Patents

Description

The present invention relates to a gymnastic apparatus or rehabilitation comprising a pneumatic cylinder, and in particular to a device with mobile counterweight and pneumatic counterbalance compensation cylinder.

The technical field of the invention is that of the manufacture of apparatus for gymnastics with pneumatic cylinder and with mobile counterweights.

The invention applies in particular - but not exclusively - to the apparatus of gymnastics comprising a device resistant to weight mounted movable substantially vertically, and further comprising a pneumatic cylinder of compensation, partial or total, of the mass of the moving weights.

US Patent 5,147,263 discloses such an apparatus wherein the pneumatic cylinder comprises, arranged inside, a double-walled cylindrical body, a piston suspended on a weight-lifting cable upwards, which is slidably mounted vertical cylindrical chamber, and a vacuum pump capable of in depression the lower part of the chamber under the piston for, attracting the piston down, exerting an effort offsetting part of the weight mass.

A disadvantage of this device is its large size resulting from the need to use a large surface piston to compensate for the level generally low depression caused by a rotor pump, the weakness depression being accentuated by the leakage resulting from the clearance provided around the piston; Another disadvantage is that this jack can only be used in vertical position.

It has been found that most ordinary pneumatic cylinders powered under pressure can not ensure a controlled effort (eg constant) the along a travel path of the resistive device (weight in particular); he was in particular, the occurrence of "hard spot" phenomena in which the cylinder unexpectedly stops the movement of the device, to the detriment of particular of its user, which is a major disadvantage.

An object of the invention is to provide an improved gymnastic apparatus and which remedies, in part at least, the disadvantages of known apparatus.

According to a first aspect, the invention consists in proposing a device for gymnastics incorporating a pneumatic jack, the jack having a piston mounted sliding in a first cylindrical chamber which is in direct communication with a second chamber, called attenuation chamber, whose volume is greater to that of the cylindrical chamber.

The presence and the large volume of the attenuation chamber, combined with means of direct communication between the two chambers, allow strongly limit the pressure fluctuations of the air contained in these chambers, particular pressure fluctuations resulting from an acceleration or Sudden deceleration of the piston, due in particular to a sudden variation of the effort exercised by a user of the device; these means therefore make it possible to avoid the appearance of "hard points" during a piston stroke in the chamber cylindrical, or at least to strongly limit them compared to the devices of gymnastics having a remote reserve of compressed air which is connected to the jack by a conduit preventing such direct communication.

Optimal results have been found in realizing the means of implementation direct communication of the two chambers in the form of at least one opening provided in the wall delimiting the cylindrical chamber, whose section has a surface at least the same order of magnitude as that of the cross section of this cylindrical chamber, in particular substantially at least equal thereto; such a opening allows the free flow of air between the two chambers, and allows by therefore, to keep both chambers at the same pressure, even at a acceleration or deceleration of the piston. Thus, all the air contained in one and the other of the two chambers contributes, by its compressibility, to the attenuation of pressure fluctuations during a variation of the piston speed.

In order to obtain a sufficient attenuation of these fluctuations, it is preferable the volume of the attenuation chamber is at least five times greater than that of the chamber receiving the piston; preferably the value of the ratio of the volume of the second bedroom to that of the first bedroom is located in a beach ranging from 5 to 30, in particular in a range from 8 to 20.

According to a preferred embodiment, each of the two chambers is cylindrical (circular section (3), or, for reasons of space, any shape such as square or rectangular section), the first chamber being delimited by a first section of tube arranged inside a second tube section delimiting the second chamber, said tube sections being coaxial; preferably, in this case, the ratio of the radius of the second tube to the radius the first tube is in a range from 3 to 6, for example about 4; this allows to limit the size of the cylinder.

Although the invention can be used with a vacuum pump arranged for being able to depress the said chambers, it is generally more advantageous to use an air compressor equipped with a compressed air buffer tank which is connected to said chambers by a conduit.

Advantageously, the gymnastic apparatus comprises a divider device of stroke, such as a hoist, which is disposed between the user operated member and the device resistant to the cylinder and, if necessary, to the weight, this makes it possible to use a jack whose course and congestion are diminished; in addition, the displacement of air in the cylinder (in mass and in flow) is also decreased, which contributes to reducing the risk of sudden surges or depressions.

The race divider may have a link, which may be a flexible link such as a cable or strap, which connects the organ to the device resistant.

The cylinder of the apparatus according to the invention may be of the double-acting type, in order to constitute a jack resistant to the effort of the user or reducing the effort assistance; For this purpose, compressed air can be selectively cylinder chamber which is situated on the side opposite that of said first chamber, with respect to the cylinder piston; however, according to a preferred embodiment, the gymnastic apparatus comprises a single acting cylinder, at least two parts heavy sliding sliders substantially vertically along two guides, the cylinder rod extending parallel to the guides, equidistant from them, and the mobile heavy parts partly extending at least around the stem and the body cylinder; this provides a compact device and simple design.

An advantage of the invention is to facilitate the implantation of the compressor to distance from the cylinder and the device, thanks to the effect of accumulation played by the chamber mitigation; this has the advantage of moving the noise source away from the user what is the compressor.

Other advantages and features of the invention will be understood through of the following description which refers to the accompanying drawings, which illustrate without any limiting character of preferential embodiments of the invention.

Unless otherwise indicated, identical or similar elements are designated in the drawings by identical references from one figure to another.

FIG. 1 is a diagrammatic perspective view of an apparatus for gymnastics according to the invention which comprises two moving heavy parts vertically and a single jack effect adapted to compensate for the mass of these parts heavy.

FIG. 2 is a diagrammatic sectional view of a simple jack the apparatus of Figure 1 and its compressed air supply circuit.

Figure 3 schematically illustrates another embodiment of an apparatus according to the invention.

With reference to FIG. 1, the apparatus 100 comprises an element 32 on which the user applies his effort; this bar-shaped element is mounted movably in rotation along the axis 99, via a bearing provided at its first end 98; the second end 97 of the bar 32 is integral with a first end a flexible transmission element 12, by a mechanical fastening 24.

The element 12 consists of a cable or a strap, is secured to the structure fixed device 100 at its second end by a fastener 22; element 12 rolls and / or slides on two bearings or pulleys 96 integral with the fixed structure of the apparatus, and on a bearing or pulley 21 integral with the movable structure of the apparatus.

The fixed structure of the apparatus comprises a base 95 able to rest on the ground, two vertical uprights 94 and an upper horizontal beam 93 receiving the fixing 22, these four pieces forming a kind of rectangular frame; two trees 92 are attached to this frame and serve to guide the mobile structure of the apparatus which is slidably mounted vertically with respect to the fixed structure.

The mobile structure comprises two heavy parts 1a and 1b suspended by their respective upper end to a horizontal beam 28; the beam 28 is secured in the middle of the pulley 21 mounted free to rotate along the horizontal axis 91 thanks to a screed (not shown); the connection between the fixed structure and the structure mobile is ensured by two bushes or sliders 90 sliding respectively on the trees 92.

The jack 2 comprises a body 2a resting by its base on the base 95, and a rod 2b whose upper end is secured to the beam 28 or in support against the lower face of it; when the cylinder is supplied with compressed air, the rod 2b exerts an ascending vertical force along the vertical axis 89 of symmetry of the part mobile device, so that the mass of the parts 1a and 1b is partly at least compensated, which requires less effort from the user to lift the parts heavy 1a, 1b; Moreover, the system constituted by the element 12, the pulleys 21, 96 and the fasteners 22, 24, form a kind of hoist which halves the effort of the user by comparison with the mass of weights 1a, 1b (after deduction of the assistance of the jack).

This force splitter device also divides the stroke of the moving structure compared to the stroke of the end 24 linked to the bar 32, which causes also a doubled velocity of the moving structure - and hence the stem of the cylinder - in comparison with the speed of said end 24 of the element 12.

Preferably, the mass, the dimensions and the spacing on both sides of the axis 89 (according to which the cylinder exerts its force) parts 1a and 1b, are substantially identical, so that the mobile structure is substantially symmetrical and balanced with respect to this axis.

With reference to FIG. 2, the body 2a of the jack 2 comprises a section 40 of metal tube of axis 89, which is closed tightly at each end by two 41 and 42 dishes. The bottom bottom 41 is pierced with an orifice equipped with a device purge, while the upper bottom 42 is pierced with a central orifice 49 and two peripheral orifices: an orifice 43 for connecting a conduit 44 to a connection apparatus 45 for displaying the pressure prevailing in the chambers of the jack, and a port 46 allowing the entry into the cylinder chambers of compressed air by a compressor 48 and transported by a conduit 47.

Through the central orifice 49 of the bottom 42 extends the upper end of a section 50 of shaft tube 89 whose lower end 51 is open and whose the upper end is partially closed by a bottom; this last bottom is equipped two large openings 52 forming venting vents (according to the arrows 56) of the upper chamber 54, and a central orifice 53 equipped a sliding bearing to allow the passage of the rod 2b through this bottom.

The rod 2b has at its upper end a connecting means 55 or bearing on the beam (28 FIG. 1), and is integral at its lower end with a piston 57 sliding in the tube 50 along the axis 89.

Part 58 of the chamber delimited by the tube 50 which is located below of the piston 57 is in free communication, through the opening 51, with the chamber attenuation 59 delimited by the tube 40 and the funds 41, 42; this volume is filled compressed air delivered at 46 when the controls 61 or 65 are actuated.

The portion 54 of the chamber defined by the tube 50 is located above the piston 57 is in free communication with the atmosphere thanks to the vents 56 whose cumulative area is preferably of the same order of magnitude as that of the section transverse of the chamber 54.

It is understood that the free flow of compressed air between chambers 58 and 59 through the opening 51, allows the attenuation and if necessary the suppression of abrupt changes in air pressure against the underside of the piston, when it undergoes an acceleration due to the movement of the user.

A solenoid valve 60 allows, by action of the user on a command 61, supplying the chambers 58, 59 with compressed air delivered by the compressor 48, by through conduits 62, 63 and 47; conversely, the action of the user on a command 65 makes it possible to evacuate from these chambers the compressed air via the ducts 47, 66 and a solenoid valve 64.

In order to increase the compactness of the apparatus, the height of the jack is chosen at a value close to that 18 of the heavy parts 1a, 1b (Figure 1), and the end bottom of the tube 50 is positioned at a short distance (along the axis 89) of the bottom 41; however, this distance is chosen to be sufficient to avoid disrupting free movement between rooms 58 and 59.

For example, the tube 50 has an inside diameter of 45 mm and the tube 40 has an inside diameter of 180 mm; the cylinder has a height of 550 mm (including the rod in the retracted position) and a stroke of 400 mm, and the ratio of the volume of the chamber 59 to the volume of the cylindrical chamber 54, 58 in which the piston 57 slides, is about 15.

With reference to FIG. 3, a jack 2a, 2b similar to that of FIG. be used without moving weight to form a pneumatic resistant device of the apparatus, which opposes a vertical downward movement of the movable pulley 21 attached to the end of the rod 2b, when the user moves the operating member 32 according to the arrow 101.

In this configuration, the flexible link 12 and its fixed fasteners 22 and mobile 24 form, with the fixed and movable pulleys 96 and 21, a device dividing by two the effort: the resistive force of the jack is twice that exerted by the user.

Claims (10)

1. An exercise apparatus (100) comprising a drive member (32) connected to a pneumatic actuator (2), the actuator comprising a piston (57) slidably mounted in a first chamber (54, 58), the apparatus being characterized in that the first chamber is in direct communication with an attenuation chamber (59) of volume greater than that of the first chamber.
2. A pneumatic-actuator exercise apparatus according to claim 1, in which the wall of the first chamber includes an opening (51) providing communication with the attenuation chamber, the opening being of section that is not less than the section of the first chamber.
3. A pneumatic-actuator exercise apparatus according to claim 1 or claim 2, in which the volume of the attenuation chamber is at least five times greater than the volume of the first chamber.
4. A pneumatic-actuator exercise apparatus according to any one of claims 1 to 3, in which each of the two chambers is cylindrical and of circular section, the first chamber being defined by a first segment of tube (50) placed inside a second segment of tube (40) defining the second chamber, said segments of tube being coaxial.
5. A pneumatic-actuator exercise apparatus according to claim 4, in which the ratio of the radius of the second tube to the radius of the first tube lies in the range 3 to 6.
6. A pneumatic-actuator exercise apparatus according to any one of claims 1 to 5, the apparatus including an air compressor (48) fitted with a buffer tank of compressed air which is connected via a duct (62, 63, 47) to said attenuation chamber (59).
7. A pneumatic-actuator exercise apparatus according to any one of claims 1 to 6, including a force and stroke divider device between the member (32) actuated by the user and the resisting device comprising an actuator, and where appropriate a weight, which divider device includes a link that may be a flexible link (12) such as a cable or a strap connecting the member (32) to the resisting device (1a, 1b, 2).
8. A pneumatic-actuator exercise apparatus according to any one of claims 1 to 7, including at least two weight portions (1a, 1b) mounted to slide substantially vertically along two guides (92), the rod (2b) of the actuator extending parallel to the guides, and at equal distances therefrom.
9. A pneumatic-actuator exercise apparatus according to any one of claims 1 to 8, including at least two weight portions (1 a, 1b) movable in vertical translation and extending at least in part around the rod (2b) and the cylinder (2a) of the actuator (2).
10. A pneumatic-actuator exercise apparatus according to any one of claims 1 to 9, in which the actuator (2) extends under a beam (28) from which there are suspended and/or secured two weight portions (1a, 1b) that are movable in vertical translation.

Images