JP3928637B2 - thermostat - Google Patents

Description

  The present invention relates to a thermostat having a defrosting function such as a pushbutton for defrosting operation used in a refrigerator or the like.

  Conventionally, this type of thermostat has a function of removing frost adhering to a refrigerator cooler by controlling a circuit of a cooling compressor by operating a push button (see, for example, Patent Document 1).

  7 and 8 show a conventional thermostat described in Patent Document 1. FIG.

  As shown in FIG. 7 and FIG. 8, one end 2a of a lever 2 is pivotally supported on a container frame 1 made of a U-shaped box, and the other end is engaged with an opening / closing spring 3, so that the lever A compression spring 5 with one end held on a spring receiver 4 provided at an intermediate portion of 2 is installed opposite to a bellows 6, and a contact (movable contact 7, fixed contact 8) arm 9 for opening / closing a contact at the tip of the lever 2. The other end of the compression spring 5 is pivotally supported so that the one end 10a can be rotated, and the other end is brought into contact with the cam surface of the displacement cam 11 having the through hole 11a. One end 12a is pivotally supported, and the other end is provided with a deflation member 12 provided with a contact portion 12b so as to be in contact with the lever. The deflation member 12 is provided at the end of the deflation member 12. One end of the wire spring 13 to be reversed is engaged, and the spring receiving portion 14 of the cam 11 A return spring 16 is provided between the button 15, a differential pin 17 having the push button 15 attached thereto is inserted into the cam 11, an adjustment plate 18 is connected to the adjustment lever 10, and the tip of the adjustment plate 18 is opposed to the differential pin 17. It is configured to be disposed at a position in contact with the deflation bar 12.

  The operation of the thermostat configured as described above will be described below.

  First, when the temperature of the temperature sensing part rises, the pressure of the gas in the capillary tube (not shown) rises, causing the bellows 6 to expand. As a result, the spring receiver 4 is pushed up against the force of the compression spring 5 and the lever 2 is rotated in the direction of the arrow by the action of the force of the opening and closing spring 3 and is stopped by hitting a stopper (not shown). Accordingly, the arm 9 is detached from the contact plate (not shown), and the movable contact 7 is bonded to the fixed contact 8 to form an on circuit. When the temperature of the temperature sensing portion decreases, the bellows 6 contracts, the spring receiver 4 descends due to the force of the compression spring 5, and the lever 2 rotates in the direction of the opposite arrow due to the decrease in the acceleration force of the opening and closing spring 3. . At the same time, the arm 9 descends and hits a contact plate (not shown) to push it down, thereby separating the movable contact 7 from the fixed contact 8 as shown. That is, an off circuit is formed. At this time, the lever 2 is stopped by a stopper (not shown).

  The above is a general action of the thermostat due to temperature. Next, the action of the push button operation will be described. If the push button 15 is pushed down against the force of the return spring 16, the differential pin 17 is lowered, the deflation bar 12 is lowered along with it, and the deflation pin 17 is further lowered, so that the deflation bar 12 is lowered by the reversing action of the wire spring 13. The contact portion 12b of the deflation bar 12 contacts the lever 2, forcibly turns the lever 2 downward, opens the contact 7 and the contact 8, and an off circuit is formed. When the pressing of the push button 15 is released, the push button 15 and the differential pin 17 return to their original positions by the action of the return spring 16.

  On the other hand, the contact 7 and the contact 8 which are turned off by the operation of the push button 15 are closed as follows.

That is, when the temperature becomes higher than the initial temperature, the lever 2 starts to rotate upward against the force of the wire spring 13 and the downward acceleration force of the opening / closing spring 3 and the wire spring 13 is reduced, so that the lever 2 is rapidly reversed to close the contacts 7 and 8 to form an ON circuit, and the deflation bar 12 is pushed back by the lever 2 and returns to its original position by the action of the wire spring 13.
Japanese Utility Model Publication No. 57-6029

  However, in the above conventional configuration, the dimensional accuracy and surface of the push button 15, the through hole 11a of the cam 11, the dimensional variation of the return spring 16, the surface state, etc., that is, the outer wall surface of the push button 15 and the inner wall of the through hole 11a of the cam 11. If the frictional force due to the state, or the dimensional accuracy of the inner wall of the through hole 11a of the cam 11 and the outer diameter portion of the return spring 16 and the frictional force due to the surface state become excessive, the return spring is released even after the push button 15 is pressed and released. 16 does not function, the differential pin 17 and the push button 15 do not return to their original positions, and when the contact 7 and the contact 8 that are turned off are turned on at a high temperature, that is, when the differential lever 12 pushes up the differential pin 17, The excessive sliding frictional force described above prevents the reversing force of the deflation bar 12 and, at the same time, acts in the direction of hindering the reversing force of the lever 2, so that the contacts 7 and 8 are returned from OFF to ON. That the temperature has been a problem that is affecting the frictional force, i.e. there is a possibility that the recovery temperature varies.

  The present invention solves the above-described conventional problems, and the return-on temperature after defrosting by pushing a push button or the like is stable with little variation in operation, and stable defrosting of the refrigerator is achieved. The purpose is to provide a thermostat.

  In order to solve the above-described conventional problems, the thermostat of the present invention is provided with an L-shaped lever for operating the switch, a differential pin inserted into the through hole of the cam, and an arm that can contact the L-shaped lever. In an arrangement in which a pivotable pivotally supported deflation member and an end of a differential pin are engaged so as to face the end surface of the deflation bar, an elastic body having a spring property is provided on the end surface portion facing the deflation bar of the switch. It is provided so that it can come into contact.By the elastic body before the differential pin is pushed, the deflation lever is rotated and the differential pin is pushed upward to always maintain a stable differential pin position. Since the dynamic friction points are only the cam inner wall and the differential pin, an excessive sliding frictional force is not generated when the differential lever pushes up the differential pin. Inverting force that is prevented is small, i.e., it can be suppressed without being affected by the frictional force due to operation at Defupin 押時 and return, the change in the return-on temperature, variations.

  The thermostat of the present invention does not generate excessive sliding friction force when the diff pin pushes up the diff pin at the time of pushing the def pin and when returning, enabling smooth deflation reversal operation and realizing a stable return on temperature with little variation in operation. Therefore, defrosting of the refrigerator can be surely realized.

  According to the first aspect of the present invention, there is provided a substantially U-shaped container frame having a bottom portion and two opposing side surfaces, a bellows that expands and contracts by sensing a change in the internal temperature, and a lower end that contacts the bellows. Includes an L-shaped lever for operating the switch, an adjustment lever whose inclination changes by rotation of a cam having a through hole, and a spring that couples the L-shaped lever and the adjustment lever to counter the change in bellows. An adjustment plate for holding a roller body, one end of which is locked to the adjustment lever and the other end of which is rotatably locked, an adjustment screw that can change a distance between the adjustment lever and the adjustment plate, A differential pin that is inserted into the through hole of the cam and is movable up and down; a claw portion that is pivotally supported so that one end portion can be pivoted and has an inclined surface that can come into contact with the roller body; and the L-shaped An arm that can contact the lever is installed. In the thermostat in which the end portion of the differential pin is engaged so that the end portion of the differential pin is opposed to the end surface of the deflever, an elastic body having a spring property is provided on the end surface portion of the switch facing the deflever. By providing it so that it can come into contact, the deflation lever is rotated by the elastic body before the diff pin is pushed and the def pin is pushed upward to maintain a stable def pin position. When the def pin is pushed, the def flavor pushes the diff pin up. Without excessive sliding friction force, and in the direction that hinders the reversal force of the deflation lever, it is less affected by the friction force due to the operation of the differential pin and when returning, Variations can be suppressed.

  According to a second aspect of the present invention, in the thermostat of the first aspect of the invention, the elastic body is angled so that one end can be in contact with the deflation, and the other end is formed on a switch end surface portion. By providing a hole into which the protrusion of the switch end surface can be inserted so that the protrusion can be thermally fixed, the elastic body is securely fixed to the switch end surface, and the elastic body and the deflation Makes it possible to achieve a stable return-on temperature with little variation in operation during operation of the deflavor.

  According to a third aspect of the present invention, in the thermostat of the first or second aspect of the present invention, a rib capable of abutting against one end of the elastic body is provided in the vicinity of the protruding portion of the switch end surface portion. Since the body can be reliably brought into contact with the switch end face portion without any positional deviation at the contact point of the deflation bar, a stable differential pin position can be always secured.

  According to a fourth aspect of the present invention, in the thermostat of the first aspect of the invention, the elastic body is angled by providing a slope on a surface of the switch end surface where the one end of the elastic body is installed. It is possible to make contact with the deflation bar without performing the operation, and it is not necessary to consider the angle variation of the elastic body itself, so that the contact with the deflation bar can be made surely and a stable diff pin position can be always secured. .

  According to a fifth aspect of the present invention, in the thermostat of the first aspect of the invention, the elastic body is made of the same resin body as the switch end face portion, so that the number of parts and the number of assembling steps are reduced. Can be a thing.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the same reference numerals are given to the same configurations as those of the conventional example or the above-described embodiments, and detailed description thereof will be omitted. The present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a front cross-sectional view showing a state before a differential pin is pushed by a thermostat according to Embodiment 1 of the present invention. FIG. 2 is a front cross-sectional view showing a state when the differential pin of the thermostat of the embodiment is pressed. FIG. 3 is a perspective view of the switch showing a state where the elastic body of the thermostat of the embodiment is fixed. FIG. 4 is a perspective view of the switch showing a state in which the rib for preventing deviation of the thermostat of the embodiment is provided. FIG. 5 is a side view of the switch showing a state in which a slope is provided on the switch end surface of the thermostat of the same embodiment. FIG. 6 is a perspective view of the switch showing a state where the elastic body of the thermostat of the same embodiment is integrally formed.

  As shown in FIG. 1 to FIG. 6, 21 is a container frame, 22 is a bellows that expands and contracts by detecting the internal temperature, and a capillary tube 23 is connected to the bellows 22.

  Reference numeral 24 denotes an L-shaped lever that is rotatably provided by a fulcrum 24a. The lower end 24b of the L-shaped lever 24 abuts on the free end 22a of the bellows 22, and the other end 24c has a fixed contact 25. And a spacer 28 for performing a switching operation of a switch 27 for opening and closing the movable contact 26 is engaged. Further, one end of the temperature setting spring 29 is locked to the one end 24d.

  The other end of the temperature setting spring 29 is locked to an adjustment lever 31 via an adjustment screw 30, and the adjustment lever 31 is rotatably provided on the casing 21 by a lower fulcrum 31 a, and its upper end is a through hole 32. Is pressed against the temperature setting cam 33. Reference numeral 34 denotes an adjustment plate that holds one end of the adjustment lever 31 and the other end of the roller body 35 that is rotatably locked. The adjustment plate 34 has a gap between the adjustment lever 31 and the adjustment plate 34. An adjustment screw 36 that can be changed is held.

  Reference numeral 37 denotes a deflation bar that is rotatably provided by a fulcrum 37a. The deflation bar 37 is inserted into the through hole 32 of the cam 33, engages with the differential pin 38 so as to be movable up and down, and can contact the roller body 35 at one end. A claw portion 37b having a sloped body, an arm 37c that can come into contact with the adjustment lever 31 at the other end, and an L-shaped bending that can come into contact with an elastic body 39 having a spring property provided on the end surface portion 27a of the switch 27 It has the structure which has the part 37d.

  As shown in FIG. 4, the end surface portion 27a of the switch 27 has a projection 27c and a rib 27d. The elastic body 39 has a hole 39a into which the projection 27c can be inserted, and the rib 27d It is provided so as to be able to contact one end of the elastic body.

  Further, as shown in FIG. 5, a slope 27 e is provided on the surface on which one end of the elastic body 39 on the end surface portion 27 a of the switch 27 is installed.

  Further, as shown in FIG. 6, the resin elastic body 39 b is obtained by integrally molding the elastic body 39 with the same material as that of the end surface portion 27 a of the switch 27.

  The operation of the thermostat configured as described above will be described below.

  First, when the temperature of the temperature sensing part rises, the gas pressure in the capillary tube 23 rises, causing the bellows 22 to expand. As a result, the L-shaped lever 24 rotates in the direction of arrow A about the fulcrum 24a as an axis to counter the elastic force (corresponding to the set temperature) of the spring 29 set by the adjusting screw 30, and the temperature sensing unit is set. When the temperature is exceeded, the switch 27 is operated via the spacer 28, the fixed contact 25 and the movable contact 26 are turned on, and the power supply circuit is energized.

  Next, when the temperature of the temperature sensing unit decreases, the bellows 22 contracts, and the L-shaped lever 24 rotates in the direction opposite to the arrow A direction around the fulcrum 24a by the elastic force of the spring 29, and at the same time the spacer The pressure by 28 is reduced, the switch 27 is operated, the fixed contact 25 and the movable contact 26 are turned off, and the power supply circuit is turned off.

  The above is the operation due to the general temperature of the thermostat. Next, the operation due to the operation of the differential pin 38 will be described. Before the differential pin pushing operation, the elastic body 39 rotates the differential lever 37 in the direction of arrow B and pushes the differential pin 38 upward so that the position of the differential pin 38 is always kept stable. Therefore, by pressing the differential pin 38 when the switch 27 is in the on state, the deflation bar 37 performs an arc motion in the direction of arrow B around the fulcrum 37a against the force of the spring 29, and further, an L-shape is formed by the arm 37c of the deflation bar 37. By pressing the mold lever 24, the arc 27 moves counterclockwise around the fulcrum 24a of the L-shaped lever 24, so that the switch 27 is turned off via the spacer 28.

  At this time, the claw portion 37 b having the inclined surface of the deflation bar 37 is latched with the roller body 35 held by the adjustment plate 34 attached to the adjustment lever 31, and keeps the off state in the pressed position. .

  The elastic body 39 is held in a state of being pressed toward the switch 27 by the rotation of the deflation bar 37 in the direction opposite to the arrow B.

  On the other hand, when the switch 27 changes from the off-state to the on-state, the switch 27 is in the off-state, so that the bellows 22 expands due to the temperature rise of the temperature sensing section, and the L-shaped lever 24 is centered on the fulcrum 24a. Arc motion is performed in the direction of arrow A. At this time, the arm 37c of the deflation bar 37 is pushed upward by the L-shaped lever 24, and the deflation bar 37 performs an arc motion in the direction of arrow B. When a force greater than the drag force of the spring 29 is applied to the latch portion, the latch is released. The differential pin 38 returns to its original position, and the switch 27 is turned on via the spacer 28 by the rotation of the L-shaped lever 24. At this time, the elastic body 39 performs the same operation described before the operation of pushing the differential pin 38, so that the stable position of the differential pin 38 is always maintained again.

  As described above, in the present embodiment, the substantially U-shaped container frame 21 including the bottom portion and the two opposing side surfaces, the bellows 22 that expands and contracts by sensing the temperature change in the cabinet, and the bellows 22 has a lower end. The L-shaped lever 24 that contacts the other end and operates the switch 27, the adjustment lever 31 that changes its inclination by the rotation of the cam having the through hole, and the L-shaped lever 24 and the adjustment lever 31 are connected. A spring 29 that opposes the change of the bellows 22, an adjustment plate 34 that holds a roller body 35 that is locked to the adjustment lever 31 at one end and is pivotally locked at the other end, and the adjustment lever 31 and the adjustment plate 34. An adjustment screw 36 that allows the gap to be variable, a differential pin 38 that is inserted into the through hole 32 of the cam and can be moved up and down, and is pivotally supported so that one end can be rotated. Slant that can touch In a thermostat in which a claw portion 37b having a rim and an arm 37c that can contact the L-shaped lever 24 are disposed, and the end of the differential pin 38 is engaged with the end surface of the deflation bar 37 so as to face the end surface. An elastic body 39 having a spring property is provided on an end surface portion 27a of the switch 27 facing the deflation bar 37 so as to be able to contact the deflation bar 37. Before the def pin is pushed, the deflation bar 37 is rotated by the elastic body 39. When the differential pin 38 is pushed, the stable position of the differential pin 38 is maintained, and when the differential pin 38 is pushed, the friction part is only the cam inner wall and the differential pin 38, and excessive sliding friction force is generated when the differential lever 37 pushes the differential pin 38 up. It is less likely to act in the direction that hinders the reversing force of the deflation bar 37, that is, it is not affected by the friction force caused by the operation Change in return on temperature without being, it is possible to suppress variation, it is possible to provide a qualitatively good thermostat to realize less stable defrost recovery temperature of the temperature variation.

  In the present embodiment, the elastic body 39 is angled so that one end can be in contact with the deflation bar 37 and the other end can be thermally fixed to the protrusion 27c formed on the switch end surface portion 27a. By providing a hole into which the projection 27c of the switch end face can be inserted, the elastic body 39 is securely fixed and the elastic body 39 and the deflation bar 37 can be surely brought into contact with each other. Temperature can be realized.

  Further, in the present embodiment, the rib 27d that can come into contact with one end of the elastic body 39 is provided in the vicinity of the projection 27c of the switch end surface portion, so that the elastic body 39 can be securely attached to the switch end surface portion 27a without misalignment. Since contact can be made at the contact point of the deflation bar 37, a stable differential pin position can be secured at all times, and a stable return-on temperature with little variation in operation can be realized.

  In the present embodiment, the slope 27e is provided on the surface on which the one end of the elastic body 39 on the switch end surface portion 27a is installed, so that the elastic body 39 can be brought into contact with the deflation bar 37 without angling. In addition, since it is not necessary to consider the angle variation of the elastic body 39 itself, it is possible to reliably contact the deflation bar 37, to secure a stable differential pin position, and to perform a stable return with little operation variation. An on-temperature can be realized.

  In the present embodiment, the elastic body 39 is made of the same resin body as that of the switch end face portion 27a, and is integrally molded, so that the number of parts and the number of assembling steps can be reduced and the operation variation is stable. The return-on temperature can be realized.

  As described above, the thermostat according to the present invention does not generate an excessive sliding friction force when the diff pin pushes up the diff pin at the time of pushing the def pin and at the time of return. The return-on temperature can be realized and can be applied to uses such as refrigerators and cold storages.

Front sectional drawing which shows the state before the diff pin push of the thermostat in Embodiment 1 of this invention Front sectional view showing a state where the differential pin of the thermostat of the embodiment is pressed The perspective view of the switch which shows the state which fixed the elastic body of the thermostat of the embodiment The perspective view of the switch which shows the state which provided the rib for the deviation prevention of the thermostat of the embodiment The side view of the switch which shows the state which provided the slope in the switch end surface part of the thermostat of the embodiment The perspective view of the switch which shows the state which integrally molded the elastic body of the thermostat of the embodiment Front sectional view of a conventional thermostat Partial enlarged sectional view of the cam portion of a conventional thermostat

Explanation of symbols

21 Enclosure 22 Bellows 24 L-shaped lever 27 Switch 27a Switch end face portion 27c Switch end face protrusion 27d Switch end face rib 27e Switch end face slope 29 Spring 31 Adjustment lever 32 Cam through hole 33 Cam 34 Adjustment Plate 35 Roller body 36 Adjustment screw 37 Deflector 37a Deflever fulcrum 37b Deflever claw portion 37c Deflever arm 38 Def pin 39 Elastic body 39a Elastic hole 39b Resin elastic body

Claims (5)

  A substantially U-shaped container frame consisting of a bottom and two opposing side surfaces, a bellows that expands and contracts by sensing a change in the internal temperature, and an L-shape that makes the lower end abut on the bellows and operates the switch at the other end. A lever, an adjustment lever whose inclination changes by rotation of a cam having a through hole, a spring which connects the L-shaped lever and the adjustment lever to counter the change of the bellows, and one end locked to the adjustment lever The other end of the adjustment plate that holds the roller body that is pivotally locked, the adjustment screw that can change the distance between the adjustment lever and the adjustment plate, and the vertical movement through the through hole of the cam. A flexible differential pin, a claw portion that is pivotally supported so that one end can be rotated and has a slope that can contact the roller body, and an arm that can contact the L-shaped lever are provided. Place the deflation, In the thermostat in which the end portion of the differential pin is engaged so as to face the end surface of the deflation bar, an elastic body having a spring property is provided on the end surface portion of the switch facing the deflation bar so as to be in contact with the deflation bar. A thermostat characterized by that.   The elastic body is angled so that one end can come into contact with the deflation bar, and the protrusion on the switch end surface can be inserted into the other end so that it can be thermally fixed to the protrusion formed on the switch end surface. The thermostat according to claim 1, further comprising a hole.   The thermostat according to claim 1 or 2, wherein a rib capable of abutting against one end of the elastic body is provided in the vicinity of the protrusion of the switch end face.   The thermostat according to claim 1, wherein a slope is provided on a surface of the switch end surface on which one end of the elastic body is installed.   2. The thermostat according to claim 1, wherein the elastic body is integrally molded with the same resin body as that of the switch end surface portion.

Images