Cylinder device

Patent metadata

Field	Value
Publication number	US-10508665-B2
Application number	US-201615555699-A
Country	US
Kind code	B2
Filing date	Apr 6, 2016
Priority date	Apr 13, 2015
Publication date	Dec 17, 2019
Grant date	Dec 17, 2019

Abstract

In a rod hole (19) of a holding rod (18) held in a guide hole (17) of a piston (10), a limit switch (20) is fixed and a detection rod (21) is inserted. A first engagement ball (30) and a second engagement ball (40) are configured to be in contact with a first cam surface (32) and a second cam surface (42), respectively, which are provided at an outer periphery of the detection rod (21). The first engagement ball (30) and the second engagement ball (40) are configured to be in contact with a first pushing portion (35) and a second pushing portion (45), respectively, which are provided inside the guide hole (17). The position of the piston (10) is detected by electrically or electronically detecting the movement of the detection rod (21) by the limit switch (20).

First claim

The invention claimed is:

1. A cylinder device comprising:
a piston ( 10 ) inserted into a housing ( 1 );
a guide hole ( 17 ) provided in the piston ( 10 ) so as to open downward;
a holding rod ( 18 ) provided to protrude upward from a lower wall ( 4 a ) of the housing ( 1 ) so that the holding rod ( 18 ) is held in the guide hole ( 17 );
an electric or electronic switch ( 20 ) fixed to a middle-lower portion of a rod hole ( 19 ), which is provided in the holding rod ( 18 ) so as to extend in an up-down direction;
a detection rod ( 21 ) inserted ascendably and descendably into a middle-upper portion of the rod hole ( 19 ), the detection rod ( 21 ) provided to detect a position of the piston ( 10 );
a plurality of support holes ( 22 , 22 ) provided radially in the holding rod ( 18 ) at predetermined intervals with respect to a circumferential direction of the holding rod ( 18 );
a first engagement ball ( 30 ) and a second engagement ball ( 40 ) respectively inserted into the support holes ( 22 , 22 ) so as to be movable;
a first cam surface ( 32 ) configured to be in contact with the first engagement ball ( 30 ), the cam surface ( 32 ) provided at an outer periphery of the detection rod ( 21 ) so that a distance between the first cam surface ( 32 ) and an axis of the detection rod ( 21 ) increases upward;
a first pushing portion ( 35 ) configured to be in contact with the first engagement ball ( 30 ), the first pushing portion ( 35 ) provided inside the guide hole ( 17 ) so that a distance between the first pushing portion ( 35 ) and the axis decreases upward;
a second cam surface ( 42 ) configured to be in contact with the second engagement ball ( 40 ), the second cam surface ( 42 ) provided at the outer periphery of the detection rod ( 21 ) so that a distance between the second cam surface ( 42 ) and the axis decreases upward; and
a second pushing portion ( 45 ) configured to be in contact with the second engagement ball ( 40 ), the second pushing portion ( 45 ) provided inside the guide hole ( 17 ) so that a distance between the second pushing portion ( 45 ) and the axis increases upward, wherein
the position of the piston ( 10 ) is detected by electrically or electronically detecting movement of the detection rod ( 21 ) by the switch ( 20 ).

2. The cylinder device according to claim 1 , wherein
the switch ( 20 ) includes an operated component ( 20 b ) hermetically inserted into the rod hole ( 19 ) so as to be biased upward and so as to be movable in the up-down direction.

3. The cylinder device according to claim 2 , wherein:
the piston ( 10 ) includes a piston main body ( 10 a ) and a guide cylinder ( 10 b ) protruding downward from the piston main body ( 10 a ); and
a sealing member ( 47 ) is attached between an inner peripheral surface of a cylindrical bore ( 4 b ) of the housing ( 1 ) and an outer peripheral surface of the guide cylinder ( 10 b ).

4. The cylinder device according to claim 1 , wherein:
the piston ( 10 ) includes a piston main body ( 10 a ) and a guide cylinder ( 10 b ) protruding downward from the piston main body ( 10 a ); and
a sealing member ( 47 ) is attached between an inner peripheral surface of a cylindrical bore ( 4 b ) of the housing ( 1 ) and an outer peripheral surface of the guide cylinder ( 10 b ).

5. A cylinder device comprising:
a piston ( 10 ) inserted into a housing ( 1 );
a guide hole ( 17 ) provided in the piston ( 10 ) so as to open downward;
a holding rod ( 18 ) provided to protrude upward from a lower wall ( 4 a ) of the housing ( 1 ) so that the holding rod ( 18 ) is held in the guide hole ( 17 );
an electric or electronic switch ( 20 ) fixed to a middle-lower portion of a rod hole ( 19 ), which is provided in the holding rod ( 18 ) so as to extend in an up-down direction, the switch ( 20 ) including an operated component ( 20 b ) inserted into the rod hole ( 19 ) so as to be biased upward and so as to be movable in the up-down direction;
a detection rod ( 21 ) inserted ascendably and descendably into a middle-upper portion of the rod hole ( 19 ), the detection rod ( 21 ) provided to detect a position of the piston ( 10 );
a spring ( 60 ) attached to an upper portion of the rod hole ( 19 ) and configured to bias the detection rod ( 21 ) downward against a force biasing the operated component ( 20 b ) upward;
a support hole ( 22 ) provided radially in the holding rod ( 18 );
an engagement ball ( 30 ) inserted into the support hole ( 22 ) so as to be movable;
a cam surface ( 32 ) configured to be in contact with the engagement ball ( 30 ), the cam surface ( 32 ) provided at an outer periphery of the detection rod ( 21 ) so that a distance between the cam surface ( 32 ) and an axis of the detection rod ( 21 ) increases upward; and
a pushing portion ( 35 ) configured to be in contact with the engagement ball ( 30 ), the pushing portion ( 35 ) provided inside the guide hole ( 17 ) so that a distance between the pushing portion ( 35 ) and the axis decreases upward, wherein
the position of the piston ( 10 ) is detected by electrically or electronically detecting movement of the detection rod ( 21 ) by the switch ( 20 ); and
wherein the operated component ( 20 b ) is hermetically inserted into the rod hole ( 19 ) so as to be biased upward and so as to be movable in the up-down direction.

Assignees

• Kosmek Ltd

Inventors

• Kojima Ryota
• Yoshimi Masahiro
• Yokota Hideaki

Classifications

• B25B5/16

  Details, e.g. jaws, jaw attachments · CPC title

• B25B5/064

  with clamping means pivoting around an axis perpendicular to the pressing direction (B25B5/122 takes precedence) · CPC title

• B23Q17/005

  by measuring a force, a pressure or a deformation · CPC title

• B23Q3/082 Primary

  hydraulically actuated · CPC title

• B23Q3/069

  for pressing workpieces against a work-table · CPC title