Dual rate shock absorbing apparatus for a suspension system of a heavy off-road vehicle

• US 8,356,807 B2
• Filed: 06/24/2010
• Issued: 01/22/2013
• Est. Priority Date: 06/24/2010
• Status: Active Grant

• Current Assignee: Miner Elastomer Products Coporation (Miner Enterprises)
• Original Assignee: Miner Elastomer Products Coporation (Miner Enterprises)
• Inventors: Kerr, Ronald W., Beranek, Richard J.
• Primary Examiner(s): Siconolfi, Robert A
• Assistant Examiner(s): SY, MARIANO ONG
• Application Number:
  US12/803,323
• Publication Number:
  US 20110316209A1
• Time in Patent Office: 943 Days
• Field of Search: 267/293, 267/294, 267/153, 267/141.1, 267/64.26, 267/292, 267/201, 213/40.R, 213/44, 213/45, 731/170.3, 244/104.R
• US Class Current: 267/293
• CPC Class Codes: B60G 13/02 having dampers dissipating energy, e.g. frictionally
• CPC Class Codes: B60G 2300/026 Heavy duty trucks
• CPC Class Codes: F16F 1/3732 having an annular or the like shape, e.g. grommet-type resilient mountings
• CPC Class Codes: F16F 1/426 Radial flexion of ring-type springs
• CPC Class Codes: F16F 3/0873 of the same material or the material not being specified
• CPC Class Codes: F16F 3/0876 and of the same shape
• CPC Class Codes: F16F 7/00 Vibration-dampers; Shock-absorbers using fluid F16F5/00, F16F9/00; specific for rotary systems F16F15/10 ; belt tensioners F16H7/12

Abstract

A dual rate shock absorbing apparatus for a suspension system of a heavy off-road vehicle including a housing having two axially elongated members. A dual rate spring package is disposed in the housing. Such spring package includes a first spring assembly for absorbing, dissipating and returning a first predetermined level of energy imparted to the shock absorbing apparatus. One end of the first spring assembly acts against a closed end of the housing and a second end acts against a spring seat. A second spring assembly absorbs, dissipates and returns a second predetermined level of energy. One end of the second spring assembly acts against an opposed closed end of the housing and a second end acts against the spring seat. An axially elongated guide assembly, extending substantially the cumulative length of the first and second spring assemblies, controls axial compression of the first and second spring assemblies. An operable length of the guide assembly is automatically adjustable to the length of the housing during operation of the shock absorbing apparatus. An apparatus for monitoring loads applied to the shock absorbing apparatus is also provided.

Claims

1. A dual rate shock absorbing apparatus for a suspension system of a heavy off-road vehicle, comprising:

a housing including an axially elongated outer housing member having a closed end and an open end, with the closed end of said outer housing member having structure for facilitating connection of said housing to a first part on said vehicle, and with said housing further including an axially elongated inner housing member having a closed end and an open end, with lengthwise portions of the open ends of said inner and outer housing members being arranged in sliding relation relative to each other in response to loads being exerted on said absorbing apparatus, and with the closed end of said inner housing member having structure for facilitating connection of said inner housing member to a second part on said vehicle;

a spring seat arranged in an interior chamber defined by said inner and outer housing members;

a first elastomeric spring assembly arranged axially within the outer housing member for absorbing, dissipating and returning a first predetermined level of energy imparted to said shock absorbing apparatus when the closed ends of said housing members are axially compressed toward each other within a predetermined range of axial movement, with one end of said first spring assembly acting against a closed end of said outer housing member and an axially aligned second end acting against said spring seat; and

a second elastomeric spring assembly arranged axially within the inner housing member for absorbing, dissipating and returning a second predetermined level of energy different from said first predetermined level of energy imparted to said shock absorbing apparatus when the closed ends of said housing members are axially compressed toward each other;

an axially elongated guide assembly substantially extending a cumulative length of said first and second spring assemblies for controlling axial compression of said first and second spring assemblies, and with an operable length of said guide assembly being automatically adjustable to the length of said housing during operation of said shock absorbing apparatus; and

a follower carried by and toward the open end of said inner housing member such that said follower moves with said inner housing member and is operably arranged for engagement with said spring seat during operation of said shock absorbing apparatus, with said follower facilitating guidance of said inner and outer housing members relative to each other in response to axial loads being exerted upon said shock absorbing apparatus.

2. The shock absorbing apparatus according to claim 1 wherein said elongated guide assembly axially extends generally centrally through the first and second spring assemblies and said spring seat.

3. The shock absorbing apparatus according to claim 1 wherein said elongated guide assembly axially includes two axially elongated guides arranged in at least partially telescoping relation relative to each other.

4. The shock absorbing apparatus according to claim 1 further including a stop for inhibiting inadvertent axial separation of the housing members relative to each other.

5. The shock absorbing apparatus according to claim 1 further including structure arranged in axially spaced relation from said follower for axially guiding and aligning said outer housing member and said inner housing member for axial sliding movements relative to each other.

6. A dual rate shock absorbing apparatus for a suspension system of a heavy off-road vehicle, comprising:

a housing including an axially elongated outer housing member having a closed end and an open end, with the closed end of said outer housing member having structure for facilitating connection of said housing to a first part on said vehicle, and with said housing further including an axially elongated inner housing member having a closed end and an open end, with lengthwise portions of the open ends of said inner and outer housing members being arranged in sliding relation relative to each other in response to loads being exerted on said absorbing apparatus, and with the closed end of said inner housing member having structure for facilitating connection of said inner housing member to a second part on said vehicle;

a spring seat arranged in an interior chamber defined by said inner and outer housing members;

a first elastomeric spring assembly arranged axially within the outer housing member for absorbing, dissipating and returning a first predetermined level of energy imparted to said shock absorbing apparatus when the closed ends of said housing members are axially compressed toward each other within a predetermined range of axial movement, with one end of said first spring assembly acting against a closed end of said outer housing member and an axially aligned second end acting against said spring seat;

a second elastomeric spring assembly arranged axially within the inner housing member for absorbing, dissipating and returning a second predetermined level of energy different from said first predetermined level of energy imparted to said shock absorbing apparatus when the closed ends of said housing members are axially compressed toward each other;

an axially elongated guide assembly substantially extending a cumulative length of said first and second spring assemblies for controlling axial compression of said first and second spring assemblies, and with an operable length of said guide assembly being automatically adjustable to the length of said housing during operation of said shock absorbing apparatus; and

an apparatus for monitoring compressive loads applied to the shock absorbing apparatus during operation of said heavy off-road vehicle, wherein said apparatus for monitoring compressive loads includes a load cell arranged toward the closed end of at least one of the inner and outer housing members for monitoring and providing a signal indicative of the load applied to said shock absorbing apparatus, and wherein said apparatus for monitoring compressive loads includes a piston head slidably sealed to an inner periphery of at least one of the inner and outer housing members such that a pressurized fluid chamber is defined between said piston head and the closed end of said at least one of the inner and outer housing members, with said piston head being operably coupled to and movable with one of said spring assemblies, and a device for monitoring the level of pressure in said chamber and for generating a signal indicative of the level of pressure in said chamber.

7. The shock absorbing apparatus according to claim 6 wherein the device for monitoring the level of pressure in said chamber includes a pressure transducer.

8. A dual rate shock absorbing apparatus for a suspension system of a heavy off-road vehicle, comprising:

an axially elongated housing having first and second axially spaced ends, with each end of said housing having structure for facilitating connection of said shock absorbing apparatus operably between first and second parts on said vehicle, and wherein said housing includes an axially elongated inner member having a closed end and an open end and an axially elongated outer member having a closed end and an open end, with lengthwise portions of the open ends of said inner and outer members being arranged in sliding relation relative to each other;

an axially elongated elastomeric spring assembly arranged within an interior chamber defined by said housing between the closed ends of said inner and outer members, said spring assembly including a first elastomeric spring assembly for absorbing, dissipating and returning a first predetermined level of energy imparted to said shock absorbing apparatus when the closed ends of said members are axially compressed toward each other within a predetermined range of axial movement, a second elastomeric spring assembly for absorbing, dissipating and returning a second predetermined level of energy after the first predetermined level of energy imparted to said shock absorbing apparatus is exceeded, and a spring seat disposed between opposed ends of said first and second elastomeric spring assemblies;

an axially elongated guide assembly substantially extending a cumulative length of and generally centrally through said first and second spring assemblies for controlling axial compression of said first and second spring assemblies, and with an operable length of said guide assembly being automatically adjustable to the length of said housing during operation of said shock absorbing apparatus; and

a follower carried by and toward the open end of said inner member such that said follower moves with said inner member and is operably arranged for engagement with said spring seat during operation of said shock absorbing apparatus, with said follower facilitating concentric guidance of said inner and outer members relative to each other in response to axial loads being exerted upon said shock absorbing apparatus.

9. The shock absorbing apparatus according to claim 8 wherein said elongated guide assembly axially includes two axially elongated guides arranged in at least partially telescoping relation relative to each other.

10. The shock absorbing apparatus according to claim 8 further including a stop for inhibiting inadvertent axial separation of the members of said housing relative to each other.

11. The shock absorbing apparatus according to claim 8 further including structure arranged in axially spaced relation from said follower for guiding and aligning an interior periphery of said outer member and an outer periphery of said inner member for axial sliding movements relative to each other.

12. The shock absorbing apparatus according to claim 11 wherein the structure for aligning and guiding the inner and outer members relative to each other includes an annular bushing.

13. A dual rate shock absorbing apparatus for a suspension system of a heavy off-road vehicle, comprising:

an axially elongated housing having first and second axially spaced ends, with each end of said housing having structure for facilitating connection of said shock absorbing apparatus operably between first and second parts on said vehicle, and wherein said housing includes an axially elongated inner member having a closed end and an open end and an axially elongated outer member having a closed end and an open end, with lengthwise portions of the open ends of said inner and outer members being arranged in sliding relation relative to each other;

an axially elongated elastomeric spring assembly arranged within an interior chamber defined by said housing between the closed ends of said inner and outer members, said spring assembly including a first elastomeric spring assembly for absorbing, dissipating and returning a first predetermined level of energy imparted to said shock absorbing apparatus when the closed ends of said members are axially compressed toward each other within a predetermined range of axial movement, a second elastomeric spring assembly for absorbing, dissipating and returning a second predetermined level of energy after the first predetermined level of energy imparted to said shock absorbing apparatus is exceeded, and a spring seat disposed between opposed ends of said first and second elastomeric spring assemblies;

an axially elongated guide assembly substantially extending a cumulative length of and generally centrally through said first and second spring assemblies for controlling axial compression of said first and second spring assemblies, and with an operable length of said guide assembly being automatically adjustable to the length of said housing during operation of said shock absorbing apparatus; and

an apparatus for monitoring compressive loads applied to the shock absorbing apparatus during operation of said heavy off-road vehicle, wherein said apparatus for monitoring compressive loads includes a load cell arranged toward the closed end of said outer housing member for monitoring and providing a signal indicative of the load applied to said shock absorbing apparatus, and wherein said apparatus for monitoring compressive loads includes a piston head slidably sealed to an inner periphery of one of said members such that a pressurized fluid chamber is defined between said piston head and the closed end of said one of said members, with said piston head being operably coupled to and movable with one of said spring assemblies, and a device for monitoring the level of pressure in said chamber and for generating a signal indicative of the level of pressure in said chamber.

14. The shock absorbing apparatus according to claim 13 wherein the device for monitoring the level of pressure in said chamber includes a pressure transducer.

15. A dual rate shock absorbing apparatus for a suspension system of a heavy off-road vehicle, comprising:

a housing including an axially elongated outer generally cylindrical member having a closed end and an open end arranged in axially spaced relation relative to each other, and with the closed end of said outer member having structure for facilitating connection of said housing to a first part on said vehicle, and with said housing further including an axially elongated generally cylindrical inner member having a closed end and an open end arranged in axially spaced relation relative to each other, and with lengthwise portions of the open ends of said inner and outer generally cylindrical members being arranged in telescopic relation relative to each other, and with the closed end of said inner member having structure for facilitating connection of said housing to a second part on said vehicle;

structure disposed between said lengthwise portions of said inner and outer members for effecting guidance and alignment of said inner and outer members relative to each other;

a spring seat arranged in an interior chamber defined by said inner and outer members of said housing;

a first spring assembly arranged axially within the outer member for allowing said shock absorbing apparatus to yield a first spring rate when the closed ends of said members are axially compressed toward each other within a predetermined range of axial movement, with one end of said first spring assembly acting against the closed end of said outer member and an axially aligned second end acting against said spring seat, with said first spring assembly including a series of stacked individual spring pads, with each pad having an elastomeric member with a torodial configuration sandwiched between two plates, and wherein the series of axially stacked individual spring pads included in said first spring assembly are axially guided by an elongated guide axially extending from the closed end of said outer member;

a second spring assembly arranged axially within the inner member for allowing said shock absorbing apparatus to yield a second spring rate when the first spring rate of said first spring assembly is exceeded, with one end of said second spring assembly acting against the closed end of said inner member and an axially aligned second end acting against said spring seat, with said second spring assembly including a series of axially stacked individual spring pads, each pad including an elastomeric member having a torodial configuration sandwiched between two plates, and wherein the series of axially stacked individual spring pads included in said second spring assembly are axially guided by an elongated member axially extending substantially the length of said second spring assembly, and with a free end of the guide of said first spring assembly being arranged in telescoping relation with the elongated member of said second spring assembly such that axial alignment is maintained between the spring assemblies during compression of said shock absorbing apparatus; and

a follower carried by and toward the open end of inner member such that said follower moves with said inner member and is operably arranged for engagement with said spring seat during operation of said shock absorbing apparatus, with said follower facilitating concentric guidance of said inner and outer members relative to each other in response to axial loads being exerted upon said shock absorbing apparatus.

16. The shock absorbing apparatus according to claim 15 further including a stop for inhibiting inadvertent axial separation of the members of said housing relative to each other.

17. The shock absorbing apparatus according to claim 15 further including structure for guiding and aligning the open end of said inner and outer members relative to each other and relative to a central axis of said housing.

18. A dual rate shock absorbing apparatus for a suspension system of a heavy off-road vehicle, comprising:

a housing including an axially elongated outer generally cylindrical member having a closed end and an open end arranged in axially spaced relation relative to each other, and with the closed end of said outer member having structure for facilitating connection of said housing to a first part on said vehicle, and with said housing further including an axially elongated generally cylindrical inner member having a closed end and an open end arranged in axially spaced relation relative to each other, and with lengthwise portions of the open ends of said inner and outer generally cylindrical members being arranged in telescopic relation relative to each other, and with the closed end of said inner member having structure for facilitating connection of said housing to a second part on said vehicle;

structure disposed between said lengthwise portions of said inner and outer members for effecting guidance and alignment of said inner and outer members relative to each other;

a spring seat arranged in an interior chamber defined by said inner and outer members of said housing;

a first spring assembly arranged axially within the outer member for allowing said shock absorbing apparatus to yield a first spring rate when the closed ends of said members are axially compressed toward each other within a predetermined range of axial movement, with one end of said first spring assembly acting against the closed end of said outer member and an axially aligned second end acting against said spring seat, with said first spring assembly including a series of stacked individual spring pads, with each pad having an elastomeric member with a torodial configuration sandwiched between two plates, and wherein the series of axially stacked individual spring pads included in said first spring assembly are axially guided by an elongated guide axially extending from the closed end of said outer member; and

a second spring assembly arranged axially within the inner member for allowing said shock absorbing apparatus to yield a second spring rate when the first spring rate of said first spring assembly is exceeded, with one end of said second spring assembly acting against the closed end of said inner member and an axially aligned second end acting against said spring seat, with said second spring assembly including a series of axially stacked individual spring pads, each pad including an elastomeric member having a torodial configuration sandwiched between two plates, and wherein the series of axially stacked individual spring pads included in said second spring assembly are axially guided by an elongated member axially extending substantially the length of said second spring assembly, and with a free end of the guide of said first spring assembly being arranged in telescoping relation with the elongated member of said second spring assembly such that axial alignment is maintained between the spring assemblies during compression of said shock absorbing apparatus;

an apparatus for monitoring compressive loads applied to the shock absorbing apparatus during operation of said heavy off-road vehicle, with said apparatus for monitoring compressive loads including a load cell arranged toward the closed end of said outer housing member for monitoring and providing a signal indicative of the load applied to said shock absorbing apparatus, and wherein said apparatus for monitoring compressive loads includes a piston head slidably sealed to an inner periphery one of said members such that a pressurized fluid chamber is defined between said piston head and the closed end of said one of said members, with said piston head being operably coupled to and movable with one of said spring, assemblies, and a device for monitoring the level of pressure in said chamber and for generating a signal indicative of the level of pressure in said chamber.

19. The shock absorbing apparatus according to claim 18 wherein the device for monitoring the level of pressure in said chamber includes a pressure transducer.

20. A dual rate shock absorbing apparatus for a suspension system of a heavy off-road vehicle, comprising:

an axially elongated housing having first and second axially spaced ends, with each end of said housing having structure for facilitating connection of said shock absorbing apparatus operably between first and second parts on said vehicle, and wherein said housing includes an axially elongated inner member having a closed end and an open end and an axially elongated outer member having a closed end and an open end, with lengthwise portions of the open ends of said inner and outer members being arranged in sliding relation relative to each other;

an axially elongated elastomeric spring assembly arranged within an interior chamber defined by said housing between the closed ends of said inner and outer members, said spring assembly including a first elastomeric spring assembly for absorbing, dissipating and returning a first predetermined level of energy imparted to said shock absorbing apparatus when the closed ends of said members are axially compressed toward each other within a predetermined range of axial movement, a second elastomeric spring assembly for absorbing, dissipating and returning a second predetermined level of energy after the first predetermined level of energy imparted to said shock absorbing apparatus is exceeded, and a spring seat disposed between opposed ends of said first and second elastomeric spring assemblies;

an axially elongated guide assembly substantially extending a cumulative length of and generally centrally through said first and second spring assemblies for controlling axial compression of said first and second spring assemblies, and with an operable length of said guide assembly being automatically adjustable to the length of said housing during operation of said shock absorbing apparatus; and

a follower carried by and toward the open end of said inner member such that said follower moves with said inner member and is operably arranged for engagement with said spring seat during operation of said shock absorbing apparatus, with said follower facilitating concentric guidance of said inner and outer members relative to each other in response to axial loads being exerted upon said shock absorbing apparatus; and

an apparatus for monitoring compressive loads applied to the shock absorbing apparatus during operation of said heavy off-road vehicle, wherein said apparatus for monitoring compressive loads includes a flat load cell arranged toward the closed end of at least one of the inner and outer housing members for monitoring and providing a signal indicative of the load applied to said shock absorbing apparatus.

21. The shock absorbing apparatus according to claim 20 wherein said elongated guide assembly axially includes two axially elongated guides arranged in at least partially telescoping relation relative to each other.

22. The shock absorbing apparatus according to claim 20 further including a stop for inhibiting inadvertent axial separation of the members of said housing relative to each other.

23. The shock absorbing apparatus according to claim 20 further including structure arranged in axially spaced relation from said follower for guiding and aligning an interior periphery of said outer member and an outer periphery of said inner member for axial sliding movements relative to each other.

24. The shock absorbing apparatus according to claim 23 wherein the structure for aligning and guiding the inner and outer members relative to each other includes an annular bushing.