Pneumatic actuator

Patent metadata

Field	Value
Publication number	US-12066039-B2
Application number	US-202117912881-A
Country	US
Kind code	B2
Filing date	Apr 26, 2021
Priority date	Apr 26, 2020
Publication date	Aug 20, 2024
Grant date	Aug 20, 2024

Abstract

A pneumatic actuator for imparting velocity to a resting object, comprising a fixed member and a ram, the ram having two or more generally elongated ram members,
wherein the fixed member is formed with a base plate having an inlet hole therethrough, the ram members are formed and disposed concentrically about the center axis so as to lie one within another and to move in a telescopic arrangement, the innermost one of the ram members is configured to enable it to be driven by any pressurized gas fed through the inlet hole and to drive the object, and each of the other ram members is configured to move only behind the innermost ram member; the actuator being operative to move the innermost ram member along its entire range of motion and thereby impart velocity to the object.

First claim

The invention claimed is:

1. A pneumatic actuator for imparting velocity to a resting object, comprising a fixed member and a ram, the ram having two or more generally elongated ram members, each having a first end and a second end, wherein the fixed member is formed with a base plate, and with an inner cylinder and an outer cylinder, fixedly joined to the base plate concentrically about a center axis, the base plate having an inlet hole therethrough, said inlet hole being in fluid communication solely with space inside said inner cylinder, wherein the ram members are disposed concentrically about said center axis so as to lie one within another and within the outer cylinder, the first end of each ram member being disposed closer to the base plate than its second end, and to move parallel to the center axis in a telescopic arrangement, characterized in that the innermost one of said ram members is accommodated within said inner cylinder so that pressurized gas fed into inlet hole acts initially only on said innermost ram member so as to displace innermost ram member independently of the other ram members, said innermost ram member being configured so that its second end drives the object, and
wherein each of the other ram members is deployed externally to said inner cylinder so as to be acted on by the pressurized gas only after displacement of the innermost one of said ram members along said inner cylinder, so as to begin to move only after said innermost ram member is extended;
the actuator being operative, upon the feeding of pressurized gas into the inlet hole, to move said innermost ram member along its entire range of motion and thereby impart velocity to the object.

2. The actuator of claim 1 , configured so that none of said other ram members exerts a force, directly or indirectly, on said innermost ram member in a direction away from the base plate during operation.

3. The actuator of claim 2 , being further operative to have any of the ram members pull another ram member that is disposed next outside it.

4. The actuator of claim 2 , further comprising a shock absorbing system, in fluid communication with a space between said outer cylinder of the fixed member and the outermost one of said ram members, the shock absorbing system being operative to prevent said outermost ram member from moving faster than the ram member next within it.

5. The actuator of claim 1 , wherein at least two of the ram members include complementary engagement features for locking one of them to the other.

6. The actuator of claim 1 , further comprising complementary engagement features for interlocking any one of the ram members with a second ram member next outside it.

7. The actuator of claim 6 , wherein said complementary engagement features are operative to interlock said one ram member with said second ram member upon said one ram member having moved a predefined distance relative to said second ram member.

8. The actuator of claim 7 , wherein said complementary engagement features include a pin near the first end of said one ram member and a groove near the second end of said second ram member, the groove formed to accommodate said pin.

9. The actuator of claim 6 , configured so as to enable each of said other ram members to be driven by the pressurized gas while that ram member is interlocked with a ram member next within it.

10. The actuator of claim 9 , wherein the effective cross-sectional area of all the ram members that are interlocked and over which the gas exerts a pressure to effect said driving, at any time during operation, provides stepwise compensation inversely related to the average gas pressure expected at that time.

11. A system for imparting velocity to a resting object, comprising one or more actuators as in claim 1 ,
a reservoir, containing pressurized gas, and
an activation valve corresponding to each of the actuators,
wherein said reservoir is in fluid communication, through said activation valves, with the inlet holes in the corresponding actuators,
the system being operative to allow the pressurized gas to be fed into any of said inlet holes when the corresponding activation valve is open.

12. The system of claim 11 , wherein any of said actuators further comprises complementary engagement features for interlocking any one of the ram members with a second ram member next outside it.

13. The system of claim 12 , wherein said any of said actuators is configured so as to enable each of said other ram members to be driven by the pressurized gas while that ram member is interlocked with a ram member next within it.

14. The system of claim 13 , wherein, for any of said actuators, the effective cross-sectional area of all the ram members that are interlocked and over which the gas exerts a pressure to effect said driving, at any time during operation, provides stepwise compensation inversely related to the average gas pressure expected at that time.

Assignees

• Rafael Advanced Defense Systems Ltd

Inventors

• Hikind Yuval
• Shragai Rei

Classifications

• F15B21/008

  Reduction of noise or vibration · CPC title

• F15B1/26

  Supply reservoir or sump assemblies · CPC title

• F15B15/16 Primary

  of the telescopic type · CPC title

• F15B15/19

  Pyrotechnical actuators · CPC title

• F15B2211/625

  Accumulators · CPC title