JPH06103871A - Temperature sensing device - Google Patents

Abstract

PURPOSE:To provide a temp. sensing device having a switch excellent in the heat resistance and moisture-proof performance, in which the number of parts used is small, the structure is simple, and existence of object to be temp. sensed can be sensed certainly. CONSTITUTION:A movable body 2 is installed in the internal space 101 of a case 1, wherein the top 21 is protruding through an opening 103. A spring 3 applies a spring pressure directed upward to this moving body 2, and a temp. sensing element 4 is fixed to the top of the moving body 2. A switch 5 includes a stationary contact piece 51, movable contact piece 52, and another spring 53, wherein the stationary contact piece 51 is so structured that contact pieces 511, 512 are arranged at a certain spacing. The movable contact piece 52 is arranged below the movable body 52 with a gap reserved in between, and the stationary contact pieces 511, 512 are shortcircuited to each other receiving the spring pressure of the second spring 53, and the separation from them 511, 512 takes place when the movable piece 52 makes a downward motion in excess of the gap G.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature detecting device suitable for use in detecting the temperature of a cooking device such as a rice cooker or a heater.

[0002]

As a temperature detecting device of this type, a temperature sensitive element is attached to a movable body that moves forward and backward depending on the presence or absence of a body to be detected, and a switch that turns on and off by the forward and backward movement of the movable body is provided. There is known a temperature detection device configured to detect the presence or absence of a temperature-controlled object, and detect the temperature of the temperature-controlled object by a temperature sensing element when the presence of the temperature-controlled object is detected. As a known document example, the actual exploitation number is 59-132.
No. 135, Japanese Patent Publication No. 1-27729 and Japanese Utility Model Publication No. 4-19485.

In these conventional techniques, a micro switch is used as a switch for detecting an object to be detected, and the micro switch is turned on and off by the advancing and retreating motion of a movable body or is constituted by a combination of a reed switch and a magnet. The magnetic circuit between the reed switch and the magnet is controlled by the forward / backward movement of the movable body to turn the reed switch on and off.

[0004]

In this type of temperature detecting device, the switch has a small number of parts and a simple structure in order to achieve downsizing of the temperature detecting device, improvement of reliability and cost reduction. Moreover, it is desirable that the presence or absence of the object to be detected can be reliably detected, that it has excellent heat resistance and moisture resistance, and that it can operate stably even in a hot and humid atmosphere. The switch disclosed in the above-mentioned prior art does not fully satisfy this requirement.

Therefore, an object of the present invention is to reduce the number of parts, have a simple structure, and reliably detect the presence / absence of an object to be detected, have excellent heat resistance and humidity resistance, and operate stably even in a hot and humid atmosphere. A temperature detecting device having a switch is provided.

[0006]

In order to solve the above problems, the present invention is a temperature detecting device including a case, a movable body, a spring, a temperature sensitive element, and a switch, wherein the case is In the internal space of the case, the internal space has an internal space, the internal space has an opening on the upper end side, and is surrounded by a tubular portion, and the movable body can move up and down in the vertical direction. The upper end projects through the opening, the spring is provided between the case and the movable body, and applies upward spring pressure to the movable body. Attached to the upper end side of the movable body, the switch includes a fixed contact, a movable contact, and a second spring, the fixed contact is attached to the case, At least two Each of the fixed contact pieces includes a constant contact piece, and the fixed contact pieces are spaced apart from each other. The movable contactor is disposed below the movable body with a gap therebetween. In response to this, the fixed contact piece is brought into contact with the fixed contact piece to short-circuit them, and when the movable body descends beyond the gap, it is pushed by the movable body and separated from the fixed contact piece.

[0007]

In the case, the inner space is surrounded by the cylindrical portion and has an opening on the upper end side. The movable body is arranged in the inner space of the case so as to be able to move forward and backward, and the upper end is opened. Since the spring is provided between the case and the movable body and applies upward spring pressure to the movable body, the movable body has a temperature sensor such as a pan placed on its upper end. At this time, it moves downward against the spring pressure of the spring. The movable body receives the spring pressure of the spring and moves upward when the body to be measured is removed.

The switch includes a fixed contact, a movable contact, and a second spring. The fixed contact is attached to the case and includes at least two fixed contact pieces, each of the fixed contact pieces. The movable contacts are spaced from each other, and the movable contact receives the spring pressure of the second spring to contact the fixed contact piece to short-circuit the two. Performs ON operation to short-circuit one side.

The movable contact is also pushed by the movable body to move away from the fixed contact piece when the movable body descends over the gap. Therefore, when there is an object to be measured, the movable contact is moved downward by the movable body. The child moves off from the fixed contact piece. Therefore, by turning the switch on and off,
It is possible to detect the presence or absence of the test body.

The movable contact is arranged below the movable body with a gap, and when the movable body descends beyond the gap, the movable contact is pushed by the movable body and is separated from the fixed contact piece. It is possible to absorb the dimensional variation and the variation of the contact state with the object to be heated due to the variation in assembling the device by the gap, and reliably and stably maintain the on / off operation of the switch.

Since the temperature sensitive element is attached to the upper end side of the movable body, when the temperature-measured body is placed on the upper side, the temperature can be detected at a position close to the temperature-measured body.

Further, since it has a simple switch structure which is not easily affected by heat, humidity, etc., it has excellent heat resistance and humidity resistance, and operates stably even in a hot and humid atmosphere.

[0013]

1 is an exploded perspective view of a temperature detecting device according to the present invention, FIG. 2 is a partial front sectional view of the temperature detecting device shown in FIG. 1, and FIG. 3 is a usage state of the temperature detecting device shown in FIG. It is a front partial sectional view explaining. In the figure, 1 is the source,
2 is a movable body, 3 is a spring, 4 is a temperature sensitive element, 5 is a switch, and 6 is a lid. Reference numeral 7 in FIG. 3 is a temperature measuring object such as a pan.

In the case 1, the internal space 101 has a cylindrical portion 102.
Has an opening 103 on the upper end side. The tubular portion 102 has a cutout groove 104 extending in the vertical direction. The case 1 is made of an electrically insulating material having excellent heat resistance such as phenol alkyl resin. The case 1 has a mounting portion 105, and has a structure in which the mounting portion 105 is fixed to the mounting member 8 with a coupling tool 9 such as a rivet or a screw (see FIGS. 2 and 3). The mounting member 8 constitutes a bottom portion or a side surface of a heater such as a rice cooker.

The movable body 2 is arranged in the internal space 101 of the case 1 so that it can be moved forward and backward, and the upper end 21 projects through the opening 103. Movable body 2
Like the case 1, is made of an electrically insulating material such as phenol alkyl resin.

The spring 3 is provided between the case 1 and the movable body 2 and applies upward spring pressure to the movable body 2. The illustrated spring 3 has a coil shape. The case 1 has a flange portion 106 projecting inward at the bottom, and the spring 3 is arranged between the flange portion 106 and the end surface 22 of the movable body 2. The end surface 22 of the movable body 2 is composed of a tubular portion 23.

The temperature sensitive element 4 is attached to the upper end 21 side of the movable body 2. As the temperature sensitive element 4, an NTC thermistor, a PTC thermistor or the like can be used. Among these, the glass-sealed NTC thermistor is particularly preferable. The glass-sealed NTC thermistor has excellent moisture resistance and stability.
Reference numerals 41 and 42 are leads of the temperature sensitive element 4.

The switch 5 includes a fixed contact 51, a movable contact 52, and a second spring 53. The fixed contactor 51 is attached to the case 1, and at least 2
It includes one fixed contact piece 511, 512. Each of the fixed contact pieces 511 and 512 is made of a metal material that is a good electric conductor, and is arranged at a distance from each other. Each of the fixed contact pieces 511 and 512 is arranged at a position corresponding to the cutout groove 104 with a space therebetween.

The movable contactor 52 is arranged below the movable body 2 with a gap G, and receives the spring pressure of the second spring 53 to contact the fixed contact pieces 511, 512 to contact each other.
Short between 1 and 512. The movable contact 52 is pushed by the movable body 2 and separates from the fixed contact pieces 511 and 512 when the movable body 2 descends beyond the gap G.
The movable contact 52 moves up and down in the cutout groove 104, contacts the fixed contact pieces 511 and 512, and short-circuits the both 511 and 512. The movable contact 52 has a ring shape, and the movable body 2 penetrates through the inside diameter hole. The movable contactor 52 may be wholly made of a good electric conductor, or only the portions that come into contact with the fixed contact pieces 511 and 512 and the portions that electrically connect them may be made of a good electric conductor.

The second spring 53 has a coil shape,
It is arranged outside the spring 3 between the collar portion 106 and the movable contact 52.

The lid 6 is attached to the upper end 21 side of the movable body 2 and covers the temperature sensitive element 4. The lid 6 is made of, for example, aluminum or the like.

As described above, the case 1 has the internal space 101.
Is surrounded by the tubular portion 102 and has an opening 103 on the upper end side. The movable body 2 is arranged in the internal space 101 of the case 1 so as to be able to move up and down, and the upper end is the opening 103. Since the spring 3 is provided between the case 1 and the movable body 2 and exerts upward spring pressure on the movable body 2, the movable body 2 has a temperature-sensitive body 7 to be placed on its upper end. When moved, the spring 3 moves downward against the spring pressure of the spring 3, and when the object 7 to be measured is removed, the spring 3 receives the spring pressure of the spring 3 and moves upward.

Since the temperature sensitive element 4 is attached to the upper end side of the movable body 2, when the temperature-sensitive body 7 is placed on the upper end side,
The temperature sensing element 4 detects the temperature at a position close to the test body 7. In addition, the temperature sensing element 4 is damaged by the temperature-measured body 7,
It is possible to reliably prevent damage.

The switch 5 includes a fixed contact 51, a movable contact 52, and a second spring 53. The fixed contact 51 is attached to the case 1, and at least 2
Fixed contact piece 51 including two fixed contact pieces 511, 512
1 and 512 are arranged at a distance from each other, and the movable contact 52 receives the spring pressure of the second spring 53 to come into contact with the fixed contact pieces 511 and 512 to short-circuit the two. Performs an ON operation for short-circuiting between the fixed contact pieces 511-512 in the absence of the test object.

The movable contact 52 is pushed by the movable body 52 and moves away from the fixed contact pieces 511 and 512 when the movable body 2 descends beyond the gap G. The downward movement of the body 2 causes the movable contact 52 to move off from the fixed contact pieces 511 and 512 to be turned off. Therefore, it is possible to detect the presence / absence of the temperature-measured body 7 by turning on / off the switch 5.

The movable contactor 52 is arranged below the movable body 2 with a gap G therebetween, and when the movable body 2 descends beyond the gap G, the movable contactor 52 is pushed by the movable body 2 and fixed contact pieces 511, 512 are provided. Therefore, the relative relationship between the movable contact element 52 and the fixed contact pieces 511, 512 is determined by the sensor fixed position, the dimensional variation due to the variation during assembly of the device, and the variation of the contact state with the object to be heated. The gap is absorbed, and the switch on / off operation can be reliably and stably maintained.

Further, since it has a simple switch structure which is not affected by heat, humidity, etc., it has excellent heat resistance and moisture resistance,
Stable operation even in a hot and humid atmosphere.

Next, other parts shown in the drawing will be described.

A fixed contact piece 511 constituting the switch 5,
Lead wires 41 and 42 led from the temperature sensitive element 4 are connected to the respective 512. With such a structure, the sensed body 7 does not exist, the movable contact 52 is in contact with the fixed contact pieces 511, 512, and short-circuits between both 511 and 512 (see FIG. 2). The temperature element 4 is electrically short-circuited by the movable contact 52 between the fixed contact pieces 511-512. Therefore, the temperature detection signal from the temperature sensitive element 4 is not output. FIG. 4 shows an electric circuit diagram in this case.

The object to be measured 7 is placed on the upper end of the movable body 2,
When the movable body 2 moves downward and the movable contact 52 separates from the fixed contact pieces 511 and 512 (see FIG. 3), the fixed contact pieces 5 to which the lead wires 41 and 42 of the temperature sensing element 4 are connected.
The short circuit between 11, 512 is released. Therefore, when there is the temperature-measured body 7, the temperature detection signal of the temperature-measured body 7 obtained by the temperature sensing element 4 is output to the outside through the fixed contact pieces 511 and 512. FIG. 5 shows an electrical circuit diagram in this case.

Unlike the illustration, the lead wires 41 and 42 of the temperature sensitive element 4 are connected to the fixed contact pieces 511 which form the switch 5.
It is also possible to take a circuit configuration in which the fixed contact pieces 511 and 512 are electrically connected to the lead wires 41 and 42 in an external circuit by being led to the outside without being connected to each of the 512.

[0032]

As described above, according to the present invention, the following effects can be obtained. (A) In the case, the inner space is surrounded by the tubular portion and has an opening on the upper end side. The movable body is arranged in the inner space of the case so as to be able to move forward and backward, and the upper end is opened. Since the spring is provided between the case and the movable body and applies upward spring pressure to the movable body, the movable body moves up and down in the vertical direction depending on the presence or absence of the body to be measured. A temperature detecting device can be provided. (B) The fixed contact is attached to the case, includes at least two fixed contact pieces, and each of the fixed contact pieces is arranged at a distance from each other, and the movable contact has a gap below the movable body. When the movable body is moved downward beyond the gap, the fixed contact piece is separated from the fixed contact piece by receiving the spring pressure of the second spring to contact the fixed contact piece and short-circuit between them. I'm going away from
It is possible to provide a temperature detection device capable of detecting the presence or absence of the body to be detected by turning the switch on and off. (C) The movable contactor is arranged below the movable body with a gap, and when the movable body descends beyond the gap, it is pushed by the movable body and separated from the fixed contact piece. The gaps absorb the relative relationship between the contact pieces, such as the sensor fixing position, dimensional variations due to variations during device assembly, and contact state variations with the object to be heated, and the switch can be turned on reliably and stably. It is possible to provide a temperature detection device that can maintain the off operation. (D) Since the temperature sensing element is attached to the upper end side of the movable body, when the temperature-measured body is placed on the upper side, the temperature can be detected at a position close to the temperature-measured body. (E) Since it has a simple switch structure that is not affected by heat, humidity, etc., it is possible to provide a temperature detecting device which is excellent in heat resistance and humidity resistance and operates stably even in a hot and humid atmosphere.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a temperature detection device according to the present invention.

2 is a front partial cross-sectional view of the temperature detection device shown in FIG.

FIG. 3 is a front partial cross-sectional view illustrating a usage state of the temperature detecting device shown in FIG.

FIG. 4 is an electric circuit diagram of the temperature detection device shown in FIGS. 1 to 3.

FIG. 5 is an electric circuit diagram when the temperature detection device shown in FIGS. 1 to 3 detects a temperature-controlled object.

[Explanation of symbols]

 1 pc 2 Movable body 3 Spring 4 Temperature sensor 5 Switch

Claims (4)

[Claims] 1. A temperature detecting device including a case, a movable body, a spring, a temperature sensitive element, and a switch, wherein the case has an internal space, and the internal space has an opening portion on an upper end side. And is surrounded by a tubular portion, the movable body is arranged in the internal space of the case so that the movable body can be moved forward and backward, and the upper end projects through the opening. The spring is provided between the case and the movable body, applies upward spring pressure to the movable body, and the temperature sensing element is attached to the upper end side of the movable body, The switch includes a fixed contact, a movable contact, and a second spring, the fixed contact is attached to the case, includes at least two fixed contact pieces, and each of the fixed contact pieces. Are mutual The movable contactor is disposed below the movable body with a gap, and receives the spring pressure of the second spring to come into contact with the fixed contact piece so as to contact the fixed contact piece. And a temperature detecting device that is short-circuited with the movable body and is separated from the fixed contact piece by being pushed by the movable body when the movable body descends beyond the gap. 2. The case has a cutout groove along which the tubular portion extends in the vertical direction, and the fixed contactor is arranged such that each of the fixed contact pieces corresponds to the cutout groove. The temperature detector in which the movable contact moves up and down along the cutout groove. 3. The temperature detecting device according to claim 1, wherein in the fixed contact, a lead wire led from the temperature sensitive element is connected to each of the fixed contact pieces. 4. The temperature according to claim 1, wherein the case is provided with two of the cutout grooves, and each of the fixed contact pieces of the fixed contactor is individually arranged in the cutout groove. Detection device.