Assembly for producing a thermostatic element

Patent metadata

Field	Value
Publication number	US-11053928-B2
Application number	US-201716303979-A
Country	US
Kind code	B2
Filing date	May 24, 2017
Priority date	May 25, 2016
Publication date	Jul 6, 2021
Grant date	Jul 6, 2021

Abstract

This assembly comprises a cup containing a thermally-expandable material, a piston designed to move in translation along an axis (X-X) under the action of the thermally-expandable material, a guide (40) for guiding the piston and intended to be fixed to the cup, and a buffer (60) made of an elastomer material and designed to be interposed between the thermally-expandable material and the piston. The guide is provided with a bore (41) that is intended to be centered on the axis and comprises a first bore portion (41.2) having a constant cross-section, a second bore portion (41.1) provided to receive the piston and having a cross-section that is both constant and smaller than that of the first bore portion, and a third bore portion (41.3) that continuously connects the first and second bore portions. According to the invention, the buffer consists of both first and second end portions (62, 61), which, in the assembled state of the thermostatic element, are respectively received in the first and second bore portions regardless of the translational position of the piston, and of a running portion (63), which coaxially connects the first and second end portions and which, before assembly of the buffer to the rest of the thermostatic element, is at least locally thinner relative to the first end portion, so that, in the assembled state of the thermostatic element, the running portion passes from one to the other of the first and second boring portions, via the third boring portion, and partially releases the internal deformation stresses of the buffer when the piston is translated.

First claim

The invention claimed is:

1. Assembly for manufacturing a thermostatic element, comprising:
a cup which contains a thermally-expandable material,
a piston which, in an assembled state of the thermostatic element is movable relative to the cup in translation along an axis under the action of the thermally-expandable material during expansion of the thermally-expandable material,
a guide for guiding the piston in translation, wherein the guide is attached to the cup in the assembled state of the thermostatic element and is provided with a bore which, in the assembled state of the thermostatic element, is centered on the axis and which comprises three bore portions that are distinct and coaxial, namely:
a first bore portion which, in the assembled state of the thermostatic element, is axially faces the cup and has a cross-section that is substantially constant along the axis,
a second bore portion which, in the assembled state of the thermostatic element, is faces axially away from the cup and has a cross-section that is both substantially constant along the axis and smaller than the cross-section of the first bore portion, the piston being axially received in the second bore portion in an assembled state of the thermostatic element, and
a third bore portion, which connects the first and second bore portions continuously to each other, and
a buffer for transmitting motion between the thermally-expandable material and the piston, wherein the buffer is made of an elastomer material and is, in the assembled state of the thermostatic element, both axially interposed between the thermally-expandable material and the piston, and axially received in the first, second and third bore portions while being deformed therein,

characterized in that the buffer consists of:
a first end portion which, in the assembled state of the thermostatic element is received in the first bore portion regardless of the translational position of the piston,
a second end portion which, in the assembled state of the thermostatic element, is axially opposite the first end portion and is received in the second bore portion regardless of the translational position of the piston, and
a running portion, which coaxially connects the first and second end portions and which, before assembly of the buffer with the rest of the thermostatic element, is at least locally thinner with respect to the first end portion and with respect to the second end portion so that, in the assembled state of the thermostatic element, the running portion passes from one to the other of the first and second bore portions, via the third bore portion, and partially releases internal deformation stresses of the buffer when the piston is translated, wherein before assembly of the buffer to the rest of the thermostatic element, the running portion is symmetrical with respect to a median plane, which is perpendicular to the axis in the assembled state of the thermostatic element, and with respect to which the first and second end portions are symmetrical to one another, wherein before assembly of the buffer to the rest of the thermostatic element, the minimum cross-section of the first end portion and of the second end portion is substantially identical at the cross-section of the first bore portion,

and wherein the running, portion comprises:
a smallest section sub-portion which, before assembly of the buffer to the rest of the thermostatic element, presents, throughout its axial extent, a cross-section which:
is substantially constant,
corresponds to the minimum cross-section of the running portion,
is smaller than the minimum cross-section of the first end portion and of the second end portion,
is smaller than the cross-section of the first bore portion, and
is greater than the cross-section of the second bore portion;

a first connecting sub-portion, which connects the smallest section sub-portion and the first end portion and which, before assembly of the buffer with the rest of the thermostatic element, has a cross-section which varies along the axis; and
a second connecting sub-portion, which connects the smallest cross-section sub-portion and the second end portion and which, before assembly of the buffer to the rest of the thermostatic element, has a cross-section that varies along the axis.

2. Assembly according to claim 1 , wherein the axial extent of the smallest section sub-portion is reduced to a point.

3. Assembly according to claim 1 , wherein before assembly of the buffer to the rest of the thermostatic element, the cross-section of the smallest cross-section sub-portion is at least 5% smaller than the minimum cross-section of the first end portion.

4. Assembly according to claim 3 , wherein before assembly of the buffer to the rest of the thermostatic element, the cross-section of the smallest cross-section sub-portion is at least 5% smaller than the minimum cross-section of the second end portion.

5. Assembly according to claim 1 , wherein before assembly of the buffer to the rest of the thermostatic element, the smallest cross-section sub-portion presents an axial dimension that is equal to at least 75% of the axial dimension of the running portion.

6. Assembly according to claim 5 , wherein before assembly of the buffer to the rest of the thermostatic element, the smallest cross-section sub-portion has an axial dimension equal to at least 90% of the axial dimension of the running portion.

7. Assembly according to claim 1 , wherein the cross-sections of the first, second and third bore portions are of circular profile, and in that, before assembly of the buffer to the rest of the thermostatic element, the cross-sections of the first end portion of the running portion and of the second end portion have a circular profile.

8. Assembly according to claim 1 , wherein the assembly further comprises a diaphragm for sealing the thermally-expandable material, which in the assembled state of the thermostatic element is retained relative to the cup in order to prevent the thermostatic material from escaping from the cup, and is axially interposed between the thermally-expandable material and the first end portion of the buffer.

9. Assembly according to claim 1 , wherein the first and second end portions have a cross-section that is constant along the axis.

Assignees

• Vernet

Inventors

• Jager Frédéric
• Baudoin Denis

Classifications

• G05D23/02

  with sensing element expanding and contracting in response to changes of temperature (G05D23/13 takes precedence) · CPC title

• G05D23/023

  the sensing element being placed outside a regulating fluid flow · CPC title

• F03G7/06 Primary

  using expansion or contraction of bodies due to heating, cooling, moistening, drying or the like (using thermal expansion of non-vaporising liquids F01K) · CPC title

• F03G7/0645

  Clamping, fixing or crimping parts · CPC title

• F03G7/06113 Primary

  the fluids subjected to phase change · CPC title