Device having a fluid displacement volume which varies with temperature

Claim 2

A self-contained device adapted to be positioned within a fluid of varying temperature and to maintian itself in a predetermined temperature region within the fluid, said device comprising: a body member having a variable fluid displacement volume, means for sensing the temperature of the fluid, means connecting the sensing means to the body member, means connected to said body member for varying the fluid volumetric displacement of the body member in response to control by said sensing means, and said device having a weight generally equal to the weight of the volume of fluid displaced by said device when said device is submerged within the fluid at the predetermined temperature region.

Claim 3

The device of claim 1 in which resilient means urge increase in volume of the body member.

Claim 4

The device of claim 1 in which the body member includes a pair of cup-shaped elements in which one cup-shaped element is slidably movable within the other cup-shaped element, the sensing means including an actuator rod, means attaching the actuator rod to one of the cUp-shaped elements for movement thereof with respect to the other cup-shaped element to change the volume of the body member.

Claim 5

The device of claim 3 in which a resilient flexible member is attached to both of the cup-shaped elements for sealing therebetween.

Claim 6

A self-contained device adapted to move within predetermined limits of a temperature region within a fluid of varying temperature regions, said device comprising: a hollow body member having a variable fluid displacement volume, means for sensing the temperature of the fluid, means connecting the sensing means to the body member, means connected to said body member for varying the fluid volumetric displacement of the body member in response to operation of said sensing means, and said device having a weight greater than the weight of the volume of fluid displaced at one of said limits and less than the weight of the volume of fluid displaced at the other of said limits.

Claim 7

A self-contained device adapted to move within predetermined limits of a temperature region within a fluid of varying temperature regions, said device comprising: a hollow body member having a variable fluid displacement volume, means for sensing the temperature of the fluid, means connecting the sensing means to the body member, means connected to said body member for varying the fluid volumetric displacement of the body member in response to operation of said sensing means, and said device having a weight greater than the weight of the volume of fluid displaced at one of said limits and less than the weight of the volume of fluid displaced at the other of said limits.

Claim 8

The device of claim 9 which includes resilient means associated with said body member and operable upon a portion thereof for varying the volumetric displacement thereof.

Claim 9

A self-contained device adapted to be positioned within a fluid of varying temperature and to maintain itself in a predetermined temperature region within the fluid, said device comprising: a hollow body member including relatively movable wall portions forming a variable fluid displacement volume, spring means operable upon one of said wall portions for urging said wall portion in a direction to increase the fluid displacement volume of said body member, a thermally responsive actuator including a movable element and means for sensing the temperature of the fluid and for moving said element in response to changes in the temperature of the fluid, means connecting said thermally responsive actuator to said body member, means for connecting said element to one of said wall portions for varying the volumetric displacement of said body member in response to movement of said element, and said device having a weight generally equal to the weight of the volume of fluid displaced by said device when said device is submerged within the fluid at the predetermined temperature region.

Claim 10

A self-contained device adapted to be positioned within a fluid of varying temperature and to maintain itself in a predetermined temperature region within the fluid, said device comprising: a hollow body member including relatively movable wall portions forming a variable fluid displacement volume, spring means operable upon one of said wall portions for urging said wall portion in a direction to increase the fluid displacement volume of said body member, a thermally responsive actuator including a movable element and means for sensing the temperature of the fluid and for moving said element in response to changes in the temperature of the fluid, means connecting said thermally responsive actuator to said body member, means for connecting said element to one of said wall portions for varying the volumetric displacement of said body member in response to movement of said element, and said device having a weight generally equal to the weight of the volume of fluid displaced by said device when said device is submerged within the fluid at the predetermined temperature region.

Claim 11

A self-contained device adapted to be positioned within a fluid of varying temperature and to maintain itself in a predetermined temperature region within the fluid for use in fishing or the like, said device comprising: a hollow body member including a cup-like cylindrical shell, a piston movably mounted within said shell and effective to provide said body member with a variable fluid displacement volume, spring means within said shell for urging said piston in a direction to increase the fluid displacement volume of said body member, a thermally responsive actuator connected to said shell and including a case supporting a movable element, means within said case for sensing the temperature of the fluid surrounding said case and for moving said element in response to changes in the temperature of the fluid, means for connecting said element to said piston for varying the volumetric displacement of said body member in response to movement of said element, and said device having a weight generally equal to the weight of the volume of fluid displaced by said device when said device is submerged within the fluid in the predetermined temperature region.

Claim 12

A self-contained device adapted to be positioned within a fluid of varying temperature and to maintain itself in a predetermined temperature region within the fluid for use in fishing or the like, said device comprising: a hollow body member including a cup-like cylindrical shell, a piston movably mounted within said shell and effective to provide said body member with a variable fluid displacement volume, spring means within said shell for urging said piston in a direction to increase the fluid displacement volume of said body member, a thermally responsive actuator connected to said shell and including a case supporting a movable element, means within said case for sensing the temperature of the fluid surrounding said case and for moving said element in response to changes in the temperature of the fluid, means for connecting said element to said piston for varying the volumetric displacement of said body member in response to movement of said element, and said device having a weight generally equal to the weight of the volume of fluid displaced by said device when said device is submerged within the fluid in the predetermined temperature region.