Mechanically lockable universal joint and structures employing such joint

• US 7,367,740 B2
• Filed: 04/12/2004
• Issued: 05/06/2008
• Est. Priority Date: 04/10/2003
• Status: Expired due to Fees

• Current Assignee: Michael J. Lassila, Pedrag Lazic
• Original Assignee: Michael J. Lassila, Pedrag Lazic
• Inventors: Lazic, Pedrag, Lassila, Michael J.
• Primary Examiner(s): Stodola; Daniel P.
• Assistant Examiner(s): Garcia; Ernesto
• Application Number:
  US10/822,575
• Publication Number:
  US 20040202506A1
• Time in Patent Office: 1,485 Days
• Field of Search: 403/97, 403/103, 403/298, 403/359.1, 403/359.5, 403/359.6, 362/427, 248/276.1, 248/125.1, 248/125.8, 248/125.9, 285/907
• US Class Current: 403/97
• CPC Class Codes: F16C 11/10 Arrangements for locking
• CPC Class Codes: F16M 11/12 in more than one direction
• CPC Class Codes: Y10T 403/32368 including radial interengaging tongue and slot or serrations
• CPC Class Codes: Y10T 403/32418 Plural distinct positions
• CPC Class Codes: Y10T 403/559 Fluted or splined section
• CPC Class Codes: Y10T 403/7026 Longitudinally splined or fluted rod
• CPC Class Codes: Y10T 403/7033 including a lock or retainer

Abstract

An adjustable support stand for an article such as a camera employs a plurality of elongated links connected to one another at their ends by lockable universal joints. Each joint consists of a pair of complementary knuckles, each joined to a link end by a splined connection, which connections provide two axes of rotation to the joint. The knuckles are joined to one another about a third axis of rotation, perpendicular to the first two axes by means of a splined pin which passes through splined holes in the two knuckles. The splined connections employ splines of different count to achieve a high resolution of possible positions.

Claims

1. A positionally adjustable mechanism, comprising:

a pair of elongated members each having a central axis;

a base member fixed to a first end of one of the elongated members;

an article to be supported fixed to a first end of the other elongated member;

a pair of knuckles, each knuckle having an internally splined central hole;

a cylindrical pin formed with axially extending splines adapted to be inserted through said internally splined holes of the two knuckles;

a pair of structures each joining one of the knuckles to a second end of one of the elongated members so that the internally splined central hole of the knuckle extends substantially normal to the central axis of its connected elongated member, each such structure comprising a first cylindrical part having axially extending splines and a second part having a hole with internal spines, thereby allowing control of the rotational position of the first and second parts relative to one another, with the central axis of the cylindrical part and the hole being coaxial with the central axis of the connected elongated member and substantially normal to said cylindrical pin;

whereby, the orientation of the pair of elongated members relative to one another may be adjusted and fixed.

2. The adjustable mechanism of claim 1 wherein each knuckle has a planar face and its internally splined central hole is formed about an axis substantially perpendicular to the planar face, whereby the means for locking the pin in the two holes forces the planar faces of the two knuckles into abutment with one another.

3. The adjustable mechanism of claim 2 wherein at least one of the internally splined central holes which is formed substantially perpendicular to the planar face of its knuckle is angled with respect to the said planar face so that the action of locking the pin in the holes stresses the pin.

4. The adjustable mechanism of claim 1 wherein the internally splined central holes in the two knuckles are formed with different numbers of splines, the two numbers not having a common denominator, and the cylindrical pin has a head end, a first cylindrical section of larger diameter joined to the head end and formed with said axially extending splines, and a second cylindrical section of smaller diameter joined to the end of the first cylindrical section also formed with said axially extending splines, the two cylindrical sections being formed with different counts of splines, corresponding to the counts of the splines in the first and second splined central holes of the knuckles, whereby the rotational position of the knuckles may be adjusted to a resolution which represents a multiple of the two spline counts.

5. The adjustable mechanism of claim 4 wherein the angular relationship between the central hole in each of the knuckles and the center line of the splined connection between the knuckle and its associated member deviates from perpendicular, whereby upon locking the pin in the two members both the splined connection between the knuckles and their associated members and the pin connection between the two knuckles are stressed.

6. An adjustable position support stand for an article, comprising:

a pair of elongated members each having a central axis, comprising a first member and a second member;

a base for securing a first end of the first of said members to a supporting structure;

means for fixing said article to a first end of the second of said members; and

an adjustable joint for fixing the second ends of each of the pair of members to one another in a chosen positional relationship, said joint comprising;

a pair of knuckle sections, each attached to one of said members, each knuckle section having an internally splined central hole;

a cylindrical pin formed with axially extending spines adapted to be inserted through the internally splined holes of the two knuckle sections;

means for locking the pin in the holes to thereby fix the positional relationship of the two knuckle sections and their attached members; and

a pair of splined members each joining one of the knuckle sections to one of the elongated members so that the internally splined central hole of the knuckle sections extends substantially normal to the central axis of its connected elongated member, each such splined member comprising a first cylindrical part having axially extending splines and a second part having a hole with internal splines, the first part being adapted to be inserted into the hole in the second part to control the rotational position of the first and second parts, with the central axis of the cylindrical part and the hole being coaxial with the central axis of the connected elongated member and substantially normal to said cylindrical pin.

7. The adjustable position support stand of claim 6 wherein each knuckle has a planar face and the internally splined central hole of each knuckle is formed about an axis substantially perpendicular to the planar face, whereby said means for locking the pin in the holes to thereby fix the positional relationship of the two knuckles and their attached links forces said two planar faces of the two knuckles into engagement with one another.

8. The adjustable position support stand of claim 7 wherein at least one of the internally splined central holes is formed at an angle that deviates from the perpendicular to the planar face, whereby said means for locking the pin in the holes to thereby fix the positional relationship of the two knuckles and their attached members, bringing the planar faces into abutment with one another, prestresses the cylindrical pin.

9. The adjustable position support stand of claim 6 wherein the central holes formed in the two knuckles have different diameters and the splines formed in the central holes have a different spline count, without a common denominator to the two spline counts, and the cylindrical pin comprises a head, a first large diameter section extending from the head, and a second, smaller diameter section extending from the end of the first cylindrical section, the pin being adapted to pass through the central hole in one knuckle and then through the central hole in the other knuckle, and the two cylindrical sections of the pin having spline counts which correspond with the spline counts of the central holes in which the two cylindrical sections of the pin fit.