Controlled motion apparatus

• US 4,436,188 A
• Filed: 11/18/1981
• Issued: 03/13/1984
• Est. Priority Date: 11/18/1981
• Status: Expired due to Fees

• Current Assignee: Cecil R. Jones
• Original Assignee: Cecil R. Jones
• Inventors: Jones, Cecil R.
• Primary Examiner(s): Stoner, Jr., Bruce H.
• Assistant Examiner(s): Oberleitner, Robert J.
• Application Number:
  US06/322,466
• Time in Patent Office: 846 Days
• Field of Search: 188/378, 188/379, 188/380, 188/322.19, 73/663, 73/665, 73/432 K, 248/654, 248/182, 403/57, 403/58, 403/74, 308/3 R, 308/4 R
• US Class Current: 188/378
• CPC Class Codes: B06B 3/00 Methods or apparatus specially adapted for transmitting mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
• CPC Class Codes: B23Q 1/48 with sliding pairs and rotating pairs B23Q1/46 takes precedence
• CPC Class Codes: F16C 2322/39 General build up of machine tools, e.g. spindles, slides, actuators in general B23Q
• CPC Class Codes: F16C 3/035 with built-in bearings
• CPC Class Codes: G01M 7/06 Multidirectional test stands
• CPC Class Codes: Y10T 403/32041 Universal
• CPC Class Codes: Y10T 403/32181 Universal

Abstract

A controlled motion apparatus capable of at least three degrees of freedom, such as apparatus for vibration testing of equipment, comprises a support suspended from a reaction mass by three anti-rotation, linear motion displacement actuator devices each extending and movable along one axis of an XYZ coordinate system. Each actuator may be independently activated to cause the support to undergo simultaneously controlled motion along the three axes.

Claims

1. Controlled motion apparatus comprising a rigid base member, a support member, and means for mounting the support member to the rigid base for controlled motion relative to the base, said support member mounting means comprising three independently-driven displacement actuators each having a fixed part and a linearly movable part and having one of said parts connected by means of a first non-rotatable universal joint to a region of said support member and having the other of said parts connected by means of a second non-rotatable universal joint to a region of said rigid base, each of said actuators being capable upon actuation of causing a linear motion displacement of said support member along one of three orthogonal axes of an XYZ coordinate system but without permitting rotation about its respective displacement axis of the actuator movable part with respect to its fixed part or of the actuator fixed part in response to a linear displacement of the support along any of the three orthogonal axes, said non-rotating actuators by means of the first and second non-rotatable universal joint connections cooperating, during driving of the actuators to cause the said support member to undergo a controlled motion relative to the rigid base member, to maintain the support member substantially parallel to a desired plane formed by two axes of the coordinate system and to constrain the motion of said support member substantially parallel to said desired plane, and means connected to the apparatus for sensing the amount of support member displacement in its three displacement axes and generating signals representative of said displacement.

2. Controlled motion apparatus as claimed in claim 1, wherein the universal joints connected to each actuator comprises gimbal rings mounted at each actuator end with said gimbal rings each including first and second transversely-oriented gimbal pins, and means for securing the first gimbal pins of the gimbal rings at opposite ends of each actuator and means for securing the second gimbal pins of the gimbal rings to the support and base members, respectively.

3. Controlled motion apparatus as claimed in claim 1, wherein each of the actuators comprise nested tubes constituting the fixed and movable parts and having anti-rotation means, and means within the nested tubes for displacing them relative to one another, the sensing means sensing the displacement being connected to the nested tubes.

4. Controlled motion apparatus as claimed in claim 1, and further comprising means for rotating as a whole each actuator including both the fixed and movable parts and including the non-rotatable first and second universal joints about its displacement axis, said rotating means being separate from the actuator'"'"'s linear displacement.

5. Controlled motion apparatus as claimed in claim 3, wherein the anti-rotation means comprise a splining structure coupling together the nested tubes.

6. Controlled motion apparatus as claimed in claim 3, wherein the anti-rotation means comprise linear bearings coupling together the nested tubes.

7. Controlled motion apparatus as claimed in claim 4, wherein the actuator-rotating means comprise means for journalling each actuator within the rigid base member, and means coupled between the actuator and the rigid base for controllably rotating each actuator independently of the other actuators.