Claims
- 1. A method for maintaining a substantially constant load on a prime mover that is used to rotate a cam assembly, comprising the steps of:
- a. determining a net variable torque as a function of a rotational position of the cam, said net torque being developed by one or more cam followers in contact with the cam as it is rotated about an axis by the prime mover, the net torque at times being directed so as to aid the rotation and at other times being directed so as to impede the rotation of the cam by the prime mover; and
- b. providing a compensation torque that acts on the cam, the compensation torque varying with rotational position of the cam and being substantially equal but opposite in the direction in which it is applied to rotate the cam so as to substantially compensate the net torque, thereby producing the substantially constant load on the prime mover.
- 2. The method of claim 1, wherein the step of providing the compensation torque comprises the step of providing a compensation track on an end of the cam, disposed circularly about the axis around which the cam rotates the compensation track having a predefined profile that varies longitudinally in respect to the cam as a function of rotational position of the cam.
- 3. The method of claim 2, where the step of providing the compensation torque further comprises the step of biasing a roller mounted on an elastic flexure against the compensation track with sufficient force, so that as the roller rolls along the profile of the compensation track, it develops the compensation torque.
- 4. The method of claim 3, wherein the step of providing the compensation torque further comprises the step of tapering the roller so that it compensates for different linear velocities of points spaced apart radially across a width of the compensation track as the cam is rotated by the prime mover.
- 5. The method of claim 1, wherein the step of providing the compensation torque comprises the step of providing a compensation track circumferentially about the cam, the compensation track having a profile that varies with the rotational position of the cam selected so as to compensate the net torque on the cam developed by the one or more cam followers.
- 6. The method of claim 5, wherein the step of providing the compensation torque further comprises the step of biasing a roller mounted on an elastic flexure against the compensation track with sufficient force, so that as the roller rolls along the profile of the compensation track, it develops the compensation torque.
Parent Case Info
This is a divisional of the prior application Ser. No. 07/738,585, filed on Jul. 31, 1991, of Vernon R. Natwick and Michael W. Lawless for TORQUE COMPENSATED CAM ASSEMBLY AND METHOD, now U.S. Pat. No. 5,357,827, which in turn is a continuation-in-part of application Ser. No. 07/494,210 filed on Mar. 19, 1990, for VOLUMETRIC PUMP WITH SPRING-BIASED CRACKING VALVES, now U.S. Pat. No. 5,055,001, issued Oct. 8, 1991. The benefit of the filing date of these early applications is claimed under 35 U.S.C. .sctn. 120.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
4889613 |
McNeal et al. |
Dec 1989 |
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5055001 |
Natwick et al. |
Oct 1991 |
|
5059393 |
Quenin et al. |
Oct 1991 |
|
Divisions (1)
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Number |
Date |
Country |
Parent |
738585 |
Jul 1991 |
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Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
494210 |
Mar 1990 |
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