Dynamometer and coupling for a test stand

• US 4,092,855 A
• Filed: 01/28/1977
• Issued: 06/06/1978
• Est. Priority Date: 01/28/1977
• Status: Expired due to Term

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Tractor Co (Caterpillar Incorporated)
• Inventors: Kinney, Lionel L.
• Primary Examiner(s): Ruehl, Charles A.
• Application Number:
  US05/763,316
• Time in Patent Office: 494 Days
• Field of Search: 73/134, 73/135, 73/99, 73/118
• US Class Current: 73/862.09
• CPC Class Codes: G01L 3/18 mechanically actuated
• CPC Class Codes: G01M 15/02 Details or accessories of testing apparatus
• CPC Class Codes: G01M 15/044 by monitoring power, e.g. by operating the engine with one of the ignitions interrupted; by using acceleration tests

Abstract

A dynamometer including a housing comprised of first and second parts relatively rotatable about an axis and defining a chamber, at least one brake element within the chamber carried by each part, the brake elements being in adjacency and relatively movable within the chamber, a motor and spring for moving the elements to frictionally engage and disengage the same, coolant inlet and outlet ports to the chamber, and a base mounting the housing for rotation about the axis, a transducer connected to one of the housing parts and the base, and a coupling device connected to the other of the parts and including a chuck for driven engagement with a mechanical power source, the coupling being axially extendable and allowing limited play in the radial direction.

Claims

1. A dynamometer comprising:

a base;

a housing mounted on said base for rotation about an axis, said housing including first and second parts relatively rotatable about said axis and defining a chamber;

interleaved brake discs defining a brake pack within said chamber, some of said discs carried by said first housing part and others carried by said second housing part;

a hydraulic piston within said chamber for compressing said pack;

axially directed coolant inlet and outlet ports in said housing and communicating with said chamber;

a transducer connected to one of said housing parts and to said base; and

a rotatable chuck drivingly connected to the other of said housing parts.

2. The dynamometer of claim 1 wherein said chuck comprises a cylindrical element having axially directed teeth.

3. The dynamometer of claim 1 wherein said chuck is rotatable about said axis.

4. The dynamometer of claim 1 further including a pair of parallel rails, means mounting said base on said rails for sliding movement thereon, and a motor for moving said base on said rails.

5. The dynamometer of claim 4 wherein said chuck is drivingly connected to said housing other part by an axially extendable coupling, and a motor for selectively extending said coupling.

6. A dynamometer comprising:

a base;

a tubular element mounted for rotation about its longitudinal axis on said base;

a first drum secured to said tubular element on the exterior thereof and having radially directed splines on a surface thereof;

a second drum journalled on said tubular element and having radially directed splines on a surface thereof;

the splines on said drums being directed towards each other;

said drum surfaces being spaced from each other;

said drums and said surfaces defining a chamber;

a pack of brake discs within said chamber with some discs splined to said first drum and others splined to said second drum;

means for selectively compressing said pack;

a chuck for engagement with a mechanical device to be tested;

an axially extendable coupling interconnecting said chuck and said second drum;

a reciprocal motor at least partially received in said tubular element for selectively extending said coupling; and

a force measuring device connected between said base and said first drum.

7. The dynamometer of claim 6 wherein said coupling includes means allowing limited play in the radial direction so that said chuck may engage a mechanical device and align radially therewith.

8. The dynamometer of claim 7 wherein said coupling is tubular and wherein said chuck includes a cavity located on said axis;

said reciprocal motor includes a road extending through said tubular element and said coupling with its end in said cavity; and

a block loosely received, but confined within, said cavity and universally pivoted on said rod end.

9. The dynamometer of claim 6 wherein said coupling comprises a first tube having an exterior spline on one end, a second tube having an interior spline along its interior and engaged with said exterior spline, said second tube further including an exterior, spherical splined surface having its center substantially on said axis, and splines secured to said second drum engaging said spherical splined surface.

10. The dynamometer of claim 6 wherein said chamber is sealed and is adapted to receive a coolant, and further including axially directed inlet and outlet ports in fluid communication with the interior of said chamber.

11. A testing apparatus comprising:

a shaft having radially outwardly directed splines;

a first tube slidably receiving said shaft and having radially inwardly directed splines on the interior thereof in engagement with the splines on said shaft and a convex splined surface on the exterior thereof and remote from one end thereof, the center of said spherical splined surface lying on the longitudinal axis of said shaft;

one set of said radially directed splines having a relatively short axial length and the other having a relatively long axial length;

a second tube receiving said first tube and having interior splines in engagement with the convex splined surface, the remainder of the interior surface of said second tube being spaced from the exterior of said first tube;

means including a second convex splined surface having its center on said longitudinal axis and longitudinally spaced from said first tube convex splined surface;

means carried by said second tube including a splined interior surface in engagement with said second convex splined surface;

a chuck for engagement with a mechanical device to be tested, mounted and secured to said shaft; and

a dynamometer having a rotary input secured to said means including said second convex splined surface.

12. A dynamometer comprising:

a housing comprised of first and second parts relatively rotatable about an axis;

at least one brake element within said housing carried by one part and frictionally engageable with the other part;

means for moving said element to frictionally engage or disengage the same;

a base;

a bearing mounted on said base and journalling said housing for rotation, said bearing including inner and outer races, one of said races being associated with said housing and the other being associated with said base, and a plurality of rolling elements interposed between said races;

means rotatably mounting at least one of said races to the associated one of said base and said housing so that said one race may be disposed in any of a plurality of differing, angularly spaced positions about said axis with respect to the one of the housing and the base mounting the same;

a transducer connected to one of said parts and said base and restraining said housing against substantial rotation in said bearing; and

a coupling device connected to the other of said parts and including means for driven engagement with a mechanical power source.

13. The dynamometer of claim 12 wherein said mounting means comprises a ring mounting said one race and rotatably received on the associated one of said base and said housing and an exposed formation on said ring to which a relative force may be applied.

14. A dynamometer assembly comprising:

a dynamometer having a rotary input;

a chuck for engagement with a rotary power source to be tested;

an axially extendable coupling interconnecting said chuck and said dynamometer;

spring means for biasing said chuck away from said dynamometer to extend said coupling;

means mounting said dynamometer for movement along a predetermined path; and

motor means for moving said dynamometer along said path.

15. A dynamometer assembly comprising:

a dynamometer having a rotary input;

a chuck for engagement with a rotary power source to be tested;

an axially extendable coupling interconnecting said chuck and said dynamometer; and

reciprocal motor means energized to bias said chuck away from said dynamometer to extend said coupling.