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US4389781A Expired / Lapsed US ⏱️ 0.0 years remaining

Pneumatic counterbalance for a coordinate measuring machine

Assignee: Warner and Swasey Co
•
Filing: 1981-08-10
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Granted: 1983-06-28
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Expires: 2001-08-10
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Abstract

Abstract A coordinate measuring machine (10) having a vertically movable probe (41), the weight of which is offset by an improved pneumatic counterbalance (50). The pneumatic counterbalance system (50) is adapted to use a source of pressurized air (72) acting upon a ball piston (54) which is directly connected to a probe arm (42) which supports the probe (41). An accumulator (60) having a capacity large enough to insure only a small change in the counterbalanced force as the ball piston (54) moves within its cylinder (52) is provided. A valve (70) is provided in the connection of the air supply (72) to the accumulator (60). The valve (70) is adjusted to provide make up air for the air which leaks past the ball piston (54). Preferably, the accumulator (60) is formed as a pressurized plenum (60) which surrounds the cylinder (52).

Inventors

  • 👤 Robert D. Donaldson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 22:09
CPC Classifications
G; G01; G01B; G01B5/00; G01B5/0011; G01B5/0016; G01B21/00; G01B21/02; G01B21/04; Y; Y10; Y10S; Y10S33/00; Y10S33/02

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 140 words
In a coordinate measuring machine (10), including a base (20), a carriage (30) for movement relative thereto, a probe arm (42) and a probe (41) disposed at the free end of said probe arm (42) for engaging an article to be measured, characterized by: a pressurized pneumatic accumulator (60); a cylinder (52) having one end in free communication with said pneumatic accumulator (60) and the other end vented to atmosphere: a piston (54) disposed within said cylinder (52) for relative movement therein and permitting pressurized air to leak around; connecting means (56,58) connecting said piston (54) to said probe arm (54) for movement together; a regulated air supply (72); and, variable flow control valve (10) connecting said regulated air supply (72) to said accumulator (60) and being adjusted to balance for leakage past said piston (54) at a selected pressure.
Claim 2
Dependent Claim 140 words
In a coordinate measuring machine (10), including a base (20), a carriage (30) for movement relative thereto, a probe arm (42) and a probe (41) disposed at the free end of said probe arm (42) for engaging an article to be measured, characterized by: a pressurized pneumatic accumulator (60); a cylinder (52) having one end in free communication with said pneumatic accumulator (60) and the other end vented to atmosphere: a piston (54) disposed within said cylinder (52) for relative movement therein and permitting pressurized air to leak around; connecting means (56,58) connecting said piston (54) to said probe arm (54) for movement together; a regulated air supply (72); and, variable flow control valve (10) connecting said regulated air supply (72) to said accumulator (60) and being adjusted to balance for leakage past said piston (54) at a selected pressure.
Claim 3
Dependent Claim 51 words
In a coordinate measuring machine (10) as claimed in claim 1 said connecting means (56,58) is characterized by: a rod (56) connected to said piston (54); a rigid bracket (58) secured to said probe arm (42); and, swivel connecting means (53) for connecting said rod (56) to said rigid bracket (58).
Claim 4
Dependent Claim 19 words
In a coordinate measuring amchine (10) as claimed in claim 1 wherein: said piston (54) has a spherical shape.
Claim 5
Dependent Claim 45 words
A coordinate measuring machine (10) as claimed in claim 1 wherein: said accumulator (60) comprises a second cylindrical member (62) disposed around said first cylinder (52); and, the ratio of the volume of said accumulator to said first cylinder is greater than twenty to one.
Claim 6
Dependent Claim 24 words
A coordinate measuring machine as claimed in claim 1 wherein: said probe arm (42) is supported by air bearing guides for low friction movement.
Claim 7
Dependent Claim 128 words
A coordinate measuring machine for measuring an article comprising: a base; a carriage mounted on said base for relative movement therealong; a probe for engaging the article to be measured; a mounting means disposed on said carriage for supporting said probe for vertical movement with respect to said carriage comprising; a probe arm having the probe connected to one end thereof, a cylinder mounted on said carriage, a piston disposed in said cylinder for relative movement, connecting means for connecting said pistons to said probe arm for movement therewith, a pneumatic accumulator connected to one end of said cylinder to maintain the pressure within said cylinder within a predetermined range as said piston moves in said cylinder, and a source of pressurized air connected to said pneumatic accumulator.
Claim 8
Dependent Claim 128 words
A coordinate measuring machine for measuring an article comprising: a base; a carriage mounted on said base for relative movement therealong; a probe for engaging the article to be measured; a mounting means disposed on said carriage for supporting said probe for vertical movement with respect to said carriage comprising; a probe arm having the probe connected to one end thereof, a cylinder mounted on said carriage, a piston disposed in said cylinder for relative movement, connecting means for connecting said pistons to said probe arm for movement therewith, a pneumatic accumulator connected to one end of said cylinder to maintain the pressure within said cylinder within a predetermined range as said piston moves in said cylinder, and a source of pressurized air connected to said pneumatic accumulator.
Claim 9
Dependent Claim 43 words
A coordinate measuring machine as claimed in claim 6 wherein said connecting means comprises: a rigid bracket secured to said probe arm; and a rod disposed between said piston and said rigid bracket and connected by a swivel joint to said rigid bracket.
Claim 10
Dependent Claim 35 words
A coordinate measuring machine as claimed in claim 6 comprising: a variable flow control valve disposed in the connection of said air supply to said accumulator and adjusted to balance for leakage past said piston.
Claim 11
Dependent Claim 21 words
A coordinate measuring machine as claimed in claim 6 wherein: said accumulator comprises a second cylinder disposed around said first cylinder.
Claim 12
Dependent Claim 28 words
A coordinate measuring machine as claimed in claim 6 wherein: the volume of said accumulator is at least thirty times greater than the volume of said first cylinder.
Claim 13
Dependent Claim 31 words
A measuring machine as claimed in claim 10 wherein: said cylinder is at least partially disposed within said pneumatic accumulator; and connecting means for connecting said piston to said probe arm.
Claim 14
Dependent Claim 38 words
A measuring machine as claimed in claim 11 wherein said connecting means comprises: a rod secured to piston; a rigid bracket secured to said probe arm; swivel connecting means for swivel connecting said rod to said rigid bracket.
Claim 15
Dependent Claim 15 words
A measuring machine as claimed in claim 10 wherein said piston has a spherical shape.
Claim 16
Dependent Claim 21 words
A coordinate measuring machine as claimed in claim 6 comprising: air bearing guides supporting said probe arm for low friction movement.
Claim 17
Dependent Claim 125 words
A machine for measuring an article comprising: a base; a carriage disposed on said base for relative movement thereto; a probe arm supported on said carriage for movement relative thereto; a pneumatic counterbalance disposed on said carriage and connected to said probe arm comprising, a cylinder, a piston disposed in said cylinder for movement relative thereto, a pneumatic accumulator connected in free communication to one end of said cylinder to maintain the pneumatic pressure on said piston within a selected range as said piston moves in said cylinder, a source of pressurized air connected to said pneumatic accumulator, and a variable flow control valve through which said source of pressurized air is connected to said accumulator and adjusted to balance for leakage past said piston.
Claim 18
Dependent Claim 125 words
A machine for measuring an article comprising: a base; a carriage disposed on said base for relative movement thereto; a probe arm supported on said carriage for movement relative thereto; a pneumatic counterbalance disposed on said carriage and connected to said probe arm comprising, a cylinder, a piston disposed in said cylinder for movement relative thereto, a pneumatic accumulator connected in free communication to one end of said cylinder to maintain the pneumatic pressure on said piston within a selected range as said piston moves in said cylinder, a source of pressurized air connected to said pneumatic accumulator, and a variable flow control valve through which said source of pressurized air is connected to said accumulator and adjusted to balance for leakage past said piston.

References Cited (Backward Citations)

US3840993A Cited
US3818596A Cited
US4155173A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-06-27 1986-12-27 1987-06-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-06-27 1990-12-27 1991-06-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-06-27 1994-12-27 1995-06-28 $7700.00 Window Closed / Lapsed

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