CA1194046A - Pneumatic spring - Google Patents
Pneumatic springInfo
- Publication number
- CA1194046A CA1194046A CA000383065A CA383065A CA1194046A CA 1194046 A CA1194046 A CA 1194046A CA 000383065 A CA000383065 A CA 000383065A CA 383065 A CA383065 A CA 383065A CA 1194046 A CA1194046 A CA 1194046A
- Authority
- CA
- Canada
- Prior art keywords
- cylinder
- chamber
- valve
- chambers
- end wall
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Landscapes
- Presses And Accessory Devices Thereof (AREA)
Abstract
PNEUMATIC SPRING
Abstract of the Disclosure A pneumatic spring comprising an outer housing defining an open-ended outer cylinder and an inner cylinder slidingly and sealingly positioned in the outer cylinder.
The inner cylinder has a cylindrical side wall and end walls and a rod extends from the inner end wall of the outer cylinder through the inner end wall of the inner cylinder. A piston is fixed on the rod within the inner cylinder, thereby defining a first chamber between the inner end of the outer cylinder and the inner end wall on the inner cylinder and a second chamber between the piston on the rod and the outer end wall of the inner cylinder. The chambers are isolated from one another. Gaseous fluid under pressure is provided to each of the chambers independently of the other whereby when a force is applied to move the inner cylinder axially inwardly of the outer cylinder, the pressures in the two chambers are built up independently of one another.
Abstract of the Disclosure A pneumatic spring comprising an outer housing defining an open-ended outer cylinder and an inner cylinder slidingly and sealingly positioned in the outer cylinder.
The inner cylinder has a cylindrical side wall and end walls and a rod extends from the inner end wall of the outer cylinder through the inner end wall of the inner cylinder. A piston is fixed on the rod within the inner cylinder, thereby defining a first chamber between the inner end of the outer cylinder and the inner end wall on the inner cylinder and a second chamber between the piston on the rod and the outer end wall of the inner cylinder. The chambers are isolated from one another. Gaseous fluid under pressure is provided to each of the chambers independently of the other whereby when a force is applied to move the inner cylinder axially inwardly of the outer cylinder, the pressures in the two chambers are built up independently of one another.
Description
Background and Summary _ of the Invention This invention re].ates to pneumatic springs which are utilized in lieu of mechanical springs for absorbing the force of movement of two bodies as can occur in use to cushion the movement of one die with respect to another as in the clamping o a workpiece in a press for forming sheet metal parts~ Typical prior art of pneumatic springs of this type are shown in the united States Patents 3,101,194, 3,281,138, and 3,379,430.
Among the objectives or the present inv~ntion are to provide a pneumatic spring which will effectively cushion the forces; which provides two cushioning chambers which are independent of one another; and which includes chambers that will function independently of one another so that i~ there is leakage with respect to one chamber, the cushioning action of the other chamber will not be affected and which is easily maintained.
In accordance with the invention, the pneumatic spring comprises an outer housing defining an open-ended outer cylinder, and an inner cylinder slidingly and sealingly positioned in the outer cylinder. The inner cyl.inder has a cylindrical side wall and end walls. A rod extends from the inner end wall of the outer cylinder, and a piston is fixed on the rod within the inner cylinder, thereby defining a
Among the objectives or the present inv~ntion are to provide a pneumatic spring which will effectively cushion the forces; which provides two cushioning chambers which are independent of one another; and which includes chambers that will function independently of one another so that i~ there is leakage with respect to one chamber, the cushioning action of the other chamber will not be affected and which is easily maintained.
In accordance with the invention, the pneumatic spring comprises an outer housing defining an open-ended outer cylinder, and an inner cylinder slidingly and sealingly positioned in the outer cylinder. The inner cyl.inder has a cylindrical side wall and end walls. A rod extends from the inner end wall of the outer cylinder, and a piston is fixed on the rod within the inner cylinder, thereby defining a
2.
... ..... . . ....
first chamber between the inner ~nd of the outer cylinder and the inner end wall on the inner cylinder and a second chamber between the piston on the rod and the outex end wall of the inner cylinder. The chambers are isolated from one another, and valve means provide gaseous fluid under pressure to each of the chambers independently of the other whereby when a force is applied to move the inner cylinder axially inwardly of the outer cylinder, the pressures on the two chambers are built up independently of one another.
Description of the Drawings FIG. 1 is a sectional view of a pneumatic spring embodying the invention.
FIG. 2 is a similar view showing the parts in a different operative position.
FIG. 3 is a sectional view taken along the line
... ..... . . ....
first chamber between the inner ~nd of the outer cylinder and the inner end wall on the inner cylinder and a second chamber between the piston on the rod and the outex end wall of the inner cylinder. The chambers are isolated from one another, and valve means provide gaseous fluid under pressure to each of the chambers independently of the other whereby when a force is applied to move the inner cylinder axially inwardly of the outer cylinder, the pressures on the two chambers are built up independently of one another.
Description of the Drawings FIG. 1 is a sectional view of a pneumatic spring embodying the invention.
FIG. 2 is a similar view showing the parts in a different operative position.
FIG. 3 is a sectional view taken along the line
3-3 in F~G. 1.
FIG. 4 is a sectional view on an enlarged scale of a portion of the apparatus shown in FIG. 30 \
3.
o~
Des_riptlon Referring to FIG~ 1, the pneumatic spring embodying the invention is intended for use, for example, in absorbing the energy of two dies moving towa.rd one another in a press to grip the sheet metal workpiece and prevent it from slipping.
As shown in FIGS. 1 and 2, the pneumatic spring 10 comprises a housing 11 including a base 12 and a cylindrical wall 13 defining an outer open ended cylinder 14. ~ second inner cylinder 15 having a cylindrical wall 16, a closed outer end wall 17, and an inner end wall 18 is reciprocable within the outer cylinder 14 with seals 25a, 20 providing a ~luid tight seal and bearing pads 21, 22, 25b facilitating the movement. A rod or shaft 23 has one end extending into an opening 24 in the base 12 and sealed by a seal 24a and a piston 25 -fixed on the other end thereof within the chamber o the inner cylinder 15. Thus, the apparatus defines a first chamber 26 between the inner end wall 18 of the inner cylinder 15 and wall 12 of the outer cylinder 14 and a second chamber 27 between the outer end wall 17 o-f the inner cylinder 15 and piston 25.
Provision i9 made for supplying gaseous fluid under pressure to each o-f the chamber 26, 27 independently of one another and comprises a single radial inlet passage 28 that extends through a passage 29a to a transverse passage 29 to valves 30, 31. Alternatively an inlet 28a
FIG. 4 is a sectional view on an enlarged scale of a portion of the apparatus shown in FIG. 30 \
3.
o~
Des_riptlon Referring to FIG~ 1, the pneumatic spring embodying the invention is intended for use, for example, in absorbing the energy of two dies moving towa.rd one another in a press to grip the sheet metal workpiece and prevent it from slipping.
As shown in FIGS. 1 and 2, the pneumatic spring 10 comprises a housing 11 including a base 12 and a cylindrical wall 13 defining an outer open ended cylinder 14. ~ second inner cylinder 15 having a cylindrical wall 16, a closed outer end wall 17, and an inner end wall 18 is reciprocable within the outer cylinder 14 with seals 25a, 20 providing a ~luid tight seal and bearing pads 21, 22, 25b facilitating the movement. A rod or shaft 23 has one end extending into an opening 24 in the base 12 and sealed by a seal 24a and a piston 25 -fixed on the other end thereof within the chamber o the inner cylinder 15. Thus, the apparatus defines a first chamber 26 between the inner end wall 18 of the inner cylinder 15 and wall 12 of the outer cylinder 14 and a second chamber 27 between the outer end wall 17 o-f the inner cylinder 15 and piston 25.
Provision i9 made for supplying gaseous fluid under pressure to each o-f the chamber 26, 27 independently of one another and comprises a single radial inlet passage 28 that extends through a passage 29a to a transverse passage 29 to valves 30, 31. Alternatively an inlet 28a
4.
through the base 12 to passage 29a may be usedn One inlet 28, 28a is plugged when the other is used. Each valve 30, 31 is substantially ident.ical construction and comprises a body positioned in a chamber and having a passage 32 comm-
through the base 12 to passage 29a may be usedn One inlet 28, 28a is plugged when the other is used. Each valve 30, 31 is substantially ident.ical construction and comprises a body positioned in a chamber and having a passage 32 comm-
- 5 unicating with th~ passage 29, the end of which is adapted to be closed by a floating ball 33 functioning as a check valve so that when gaseous fluid under pressure is applied, the ball moves away from its seat to permit flow to a pass-age 34 and, in turn, in case of the valve 30, to an axial passage 34a through an opening 23a in the rod 23 to chamber 270 The ball 33 functions in a pilot valve 35 movable axially so that when the pressure in the chamber 27 exceeds a predetermined value, the valve 35 is moved away from its - seat 35a, permitting the gaseous fluid to be vented to the atmosphere through passage 36.
Valve 31 functions in a similar manner to permit flow to passage 37 and 38 into chamber 26 and out of chamber 26 when the pressure exceeds a predetermined value, to the passage 36.
In use, a pneumatic spring is supported so that it is generally in the position shown in FIG. 2 when the chambers 26, 27 are charged. As the dies move together, the cylinder 15 engages a clamping part o~ the die which hold the sheet metal workpiece and as the dies move closer and closer together, a greater and greater force is applied, holding 5.
the workpiece in position. Since the chambers 26, 27 are independent of one another, the p.ressures in the chambers differ but the cumulative effect is a greater sealing ~orce.
In the event th~t one or the other of the seals 25a, 20 fails, only the affected chamber will lose fluid and the other chamber will continue to function, maintaining a more limited but functional operation of a pneumatic spring. The construction permits ready disassembly of the various parts for replacement of the seals and bearings as may be required. Thus, the ring 39 which supports the wiper and bearing 21 is held in position by a snap ring 40 and removal of the snap ring 40 permits not only the ring 37 to be removed but also the cylinder 15 and the associated lower portion thereof with the seal 20 and bearing 22. This will simultaneously remo~e the shaft 23 which is slidingly positioned in the seal 24a in opening 24.
, . ~, .. .
Valve 31 functions in a similar manner to permit flow to passage 37 and 38 into chamber 26 and out of chamber 26 when the pressure exceeds a predetermined value, to the passage 36.
In use, a pneumatic spring is supported so that it is generally in the position shown in FIG. 2 when the chambers 26, 27 are charged. As the dies move together, the cylinder 15 engages a clamping part o~ the die which hold the sheet metal workpiece and as the dies move closer and closer together, a greater and greater force is applied, holding 5.
the workpiece in position. Since the chambers 26, 27 are independent of one another, the p.ressures in the chambers differ but the cumulative effect is a greater sealing ~orce.
In the event th~t one or the other of the seals 25a, 20 fails, only the affected chamber will lose fluid and the other chamber will continue to function, maintaining a more limited but functional operation of a pneumatic spring. The construction permits ready disassembly of the various parts for replacement of the seals and bearings as may be required. Thus, the ring 39 which supports the wiper and bearing 21 is held in position by a snap ring 40 and removal of the snap ring 40 permits not only the ring 37 to be removed but also the cylinder 15 and the associated lower portion thereof with the seal 20 and bearing 22. This will simultaneously remo~e the shaft 23 which is slidingly positioned in the seal 24a in opening 24.
, . ~, .. .
Claims
THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1.
A pneumatic spring for absorbing an external force by compressing a gaseous fluid trapped therein comprising an outer housing comprising a base wall and a side wall defining a first cylinder having an open end, a second cylinder slidingly and sealingly positioned in the first cylinder, seal means between said cylinders, said second cylinder having a cylindrical side wall and inner and outer end walls, a rod extending from the base wall of the first cylinder through the inner end wall of the second cylinder, a piston fixed on the rod within the second cylinder, thereby defining a first chamber between the base wall of the first cylinder and the inner end wall of the second cylinder and a second chamber between the piston on the rod and the outer end wall of the second cylinder, said chambers being isolated from one another and being normally charged with gaseous fluid such that fluid will not flow between said chambers during operation, said base wall having a single inlet and passages selectively connected to said inlet for supplying fluid under pressure to each of said chambers, a valve in each passage entirely within said base wall providing gaseous fluid under pressure to each passage such that the chambers remain isolated from one another whereby when a force is applied to move the second cylinder axially inwardly of the first cylinder, the pressures on the two chambers are built up independently of one another, each said valve including check valve means and pressure relief valve means for relieving the pressure in its respective chamber.
2.
The pneumatic spring set forth in claim 1 wherein each said valve comprises a ball check valve for controlling the flow of fluid into said chamber and a shuttle valve for controlling excessive pressure in the chamber, said ball check valve being positioned in such shuttle valve.
3.
A pneumatic spring for absorbing an external force by compensating a gaseous fluid trapped therein comprising an outer housing comprising a base wall and a side wall defining a first cylinder having an open end, a second cylinder slidingly and sealingly positioned in the first cylinder, seal means between said cylinders, said second cylinder having a cylindrical side wall and inner and outer end walls, a rod extending from the base wall of the first cylinder through the inner end wall of the second cylinder, a piston fixed on the rod within the second cylinder, thereby defining a first chamber between the base wall of the first cylinder and the inner end wall of the second cylinder and a second chamber between the piston on the rod and the outer end wall of the second cylinder, said chambers being isolated from one another and being normally charged with gaseous fluid such that fluid will not flow between said chambers during operation, said base wall having a first inlet and passages selectively connected to said inlet for supplying fluid under pressure to the valve of each of said chambers, a valve in each passage providing gaseous fluid under pressure to each passage such that the chambers remain isolated from one another whereby when a force is applied to move the second cylinder axially inwardly of the first cylinder, the pressures on the two chambers are built up independently of one another, each said valve including check valve means and pressure relief valve means for relieving the pressure in its respective chamber, each said valve comprising a ball check valve for controlling the flow of fluid into its respective chamber and a shuttle valve for controlling excessive pressure in its respective chamber, said ball check being positioned in such shuttle valve, said first inlet extending from the bottom of said base wall, said base wall including a second inlet extending from the side of said base wall and communicating with said passages such that one of the inlets can be used selectively by obstructing the other inlet.
4.
A pneumatic spring for absorbing an external force comprising an outer cylinder having a cylindrical side wall and an end wall, a piston slidingly and sealingly positioned within said cylinder to define a chamber, said piston and cylinder being adapted to be engaged by external loads so that relative axial inward movement absorbs the forces of the loads by compressing gaseous fluid trapped therein, said end wall of said outer cylinder having an inlet air passage to the chamber, and valve means entirely within said end wall between the inlet and the passage including inlet valve means within said end wall for recharging said chamber and pressure relief valve means within said end wall for relieving excessive pressure in said chamber.
5.
The pneumatic spring set forth in claim 4 including separate radial and axial inlets in said end wall extending to said valve means and adapted to be used selectively.
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1.
A pneumatic spring for absorbing an external force by compressing a gaseous fluid trapped therein comprising an outer housing comprising a base wall and a side wall defining a first cylinder having an open end, a second cylinder slidingly and sealingly positioned in the first cylinder, seal means between said cylinders, said second cylinder having a cylindrical side wall and inner and outer end walls, a rod extending from the base wall of the first cylinder through the inner end wall of the second cylinder, a piston fixed on the rod within the second cylinder, thereby defining a first chamber between the base wall of the first cylinder and the inner end wall of the second cylinder and a second chamber between the piston on the rod and the outer end wall of the second cylinder, said chambers being isolated from one another and being normally charged with gaseous fluid such that fluid will not flow between said chambers during operation, said base wall having a single inlet and passages selectively connected to said inlet for supplying fluid under pressure to each of said chambers, a valve in each passage entirely within said base wall providing gaseous fluid under pressure to each passage such that the chambers remain isolated from one another whereby when a force is applied to move the second cylinder axially inwardly of the first cylinder, the pressures on the two chambers are built up independently of one another, each said valve including check valve means and pressure relief valve means for relieving the pressure in its respective chamber.
2.
The pneumatic spring set forth in claim 1 wherein each said valve comprises a ball check valve for controlling the flow of fluid into said chamber and a shuttle valve for controlling excessive pressure in the chamber, said ball check valve being positioned in such shuttle valve.
3.
A pneumatic spring for absorbing an external force by compensating a gaseous fluid trapped therein comprising an outer housing comprising a base wall and a side wall defining a first cylinder having an open end, a second cylinder slidingly and sealingly positioned in the first cylinder, seal means between said cylinders, said second cylinder having a cylindrical side wall and inner and outer end walls, a rod extending from the base wall of the first cylinder through the inner end wall of the second cylinder, a piston fixed on the rod within the second cylinder, thereby defining a first chamber between the base wall of the first cylinder and the inner end wall of the second cylinder and a second chamber between the piston on the rod and the outer end wall of the second cylinder, said chambers being isolated from one another and being normally charged with gaseous fluid such that fluid will not flow between said chambers during operation, said base wall having a first inlet and passages selectively connected to said inlet for supplying fluid under pressure to the valve of each of said chambers, a valve in each passage providing gaseous fluid under pressure to each passage such that the chambers remain isolated from one another whereby when a force is applied to move the second cylinder axially inwardly of the first cylinder, the pressures on the two chambers are built up independently of one another, each said valve including check valve means and pressure relief valve means for relieving the pressure in its respective chamber, each said valve comprising a ball check valve for controlling the flow of fluid into its respective chamber and a shuttle valve for controlling excessive pressure in its respective chamber, said ball check being positioned in such shuttle valve, said first inlet extending from the bottom of said base wall, said base wall including a second inlet extending from the side of said base wall and communicating with said passages such that one of the inlets can be used selectively by obstructing the other inlet.
4.
A pneumatic spring for absorbing an external force comprising an outer cylinder having a cylindrical side wall and an end wall, a piston slidingly and sealingly positioned within said cylinder to define a chamber, said piston and cylinder being adapted to be engaged by external loads so that relative axial inward movement absorbs the forces of the loads by compressing gaseous fluid trapped therein, said end wall of said outer cylinder having an inlet air passage to the chamber, and valve means entirely within said end wall between the inlet and the passage including inlet valve means within said end wall for recharging said chamber and pressure relief valve means within said end wall for relieving excessive pressure in said chamber.
5.
The pneumatic spring set forth in claim 4 including separate radial and axial inlets in said end wall extending to said valve means and adapted to be used selectively.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US18013380A | 1980-08-21 | 1980-08-21 | |
| US180,133 | 1980-08-21 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1194046A true CA1194046A (en) | 1985-09-24 |
Family
ID=22659328
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000383065A Expired CA1194046A (en) | 1980-08-21 | 1981-07-31 | Pneumatic spring |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1194046A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111609073A (en) * | 2020-06-02 | 2020-09-01 | 上海应用技术大学 | Aircraft landing gear buffer |
-
1981
- 1981-07-31 CA CA000383065A patent/CA1194046A/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111609073A (en) * | 2020-06-02 | 2020-09-01 | 上海应用技术大学 | Aircraft landing gear buffer |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4550899A (en) | Pneumatic spring | |
| KR101675390B1 (en) | Reaction device for forming equipment | |
| JPH0124412Y2 (en) | ||
| US4428566A (en) | Two-tube hydropneumatic shock absorber | |
| US3379430A (en) | Twin piston pneumatic spring | |
| FI62480C (en) | SLAGANORDNING | |
| US3578014A (en) | Pressure regulator for pressurized-fluid circuits | |
| ATE135091T1 (en) | PNEUMATIC SHOCK ABSORBER | |
| JPH02102901A (en) | Method and device for filling hydropneumatic intensifying type pressure transducer with pressure oil | |
| JPH02248734A (en) | Hydraulic shock absorber | |
| GB670452A (en) | Improvements in hydraulic devices for damping oscillations for spring suspensions ofvehicles and the like | |
| US3088285A (en) | Device for varying hydraulic pressure | |
| DE50011469D1 (en) | Vehicle brake system with a gas pressure accumulator | |
| US3877344A (en) | Cushioned hydraulic actuator | |
| FI63177C (en) | HYDRAULISK SLAGANORDNING | |
| CA1194046A (en) | Pneumatic spring | |
| KR20210049935A (en) | Hydraulic cylinder | |
| US5927178A (en) | Press driven tool actuator module | |
| US4249380A (en) | Two stage intensifier | |
| US5395090A (en) | Valve for high pressure fluid systems | |
| JP4491371B2 (en) | Shock absorber | |
| US3038313A (en) | Combined air and hydraulic piston and cylinder devices | |
| US2224305A (en) | Shock absorber | |
| RU1812364C (en) | Hydraulic shock absorber | |
| SU1756462A1 (en) | Hydraulic hammer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |