JPS5848976B2 - delay relay - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a thermostatic electrical switch, particularly a delay relay (hereinafter abbreviated as TDR) that utilizes a thermostatic switch for opening and closing an electrical circuit.

) regarding. BACKGROUND OF THE INVENTION In particular, the present invention provides a method for holding certain electrical terminals of a TDR and a thermostat switch in a certain position with respect to a case by means of a retaining member configured to be fixed to each other and to a recess in the case. It concerns the TDR that is retained.

In conventional TDRs, the thermostat switch is adhesively fixed or tacked into the case, and the electrical terminals are tacked into the case.

This adhesive fixing method requires the adhesive to be cured, and the time required for this curing increases the assembly time of the unit.

Whether applying adhesives or tacking electrical terminals involved separate manufacturing steps that increased production time and cost.

That is, known assembly methods require that the components of the TDR be moved together in different axes or planes (e.g., vertical or horizontal planes), thereby preventing the unit from being rotated during the assembly operation. This increases production time and requires complex production machinery.

SUMMARY OF THE INVENTION It is an object of the present invention to simplify the assembly of delay relays and to provide a robust delay relay.

According to the present invention, the assembly process is unified to inserting and mating from a substantially vertical direction, so the assembly is significantly simplified, and since no adhesive is used, at least the time required for curing is reduced. It saves time, and because it does not use rivets, it does not require any process equipment or time, making it highly suitable for mass production.Also, the trigger piece provided on the terminal for power supply to the heater is a protrusion on the cover. Since the terminal is pressed and fixed by the member and the cover is pressed and fixed by the elastic holding member, the terminal is securely fixed, thereby providing a robust delay relay with excellent vibration resistance.

To summarize, the delay relay of the present invention includes a case having a housing portion and a terminal receiving groove within the case.

A temperature-sensitive switch that opens and closes the electrical circuit is installed inside the storage compartment.

The switch assembly has contacts and a thermostatic switch within the component, and the contacts move and engage each other in response to actuation of the thermostatic element when the element is subjected to a predetermined temperature condition. Becomes a state of detachment.

A heater energized by the second circuit is disposed in thermal communication with the switch assembly for heating the thermostatic element.

A pair of terminals configured to make electrical contact with the heater are provided within the case, and the terminals form part of the second circuit.

A heater and switch assembly is mounted within the housing, and the terminals are received by terminal receiving grooves within the case.

A cover covers the housing and has means engageable with the terminal, thereby retaining the terminal within the case.

A retaining member engageable with the case is pressed into the entry position of the receptacle to retain the cover switch assembly, heater and terminals in assembled relationship with each other within the case.

The method of the present invention for assembling a delay relay unit includes the following steps.

First, the terminal member having the portion extending into the storage portion is inserted into the case.

The heater and switch assembly is then inserted into the housing such that the switch assembly and heater are in thermal communication and the heater is in electrical contact with the terminal portion.

The cover is then installed into the housing and covers the switch assembly and heater, the cover being in engagement with the terminal member.

Further, the retaining member is engageable with the case at the side of the housing, thereby securing the terminal member, heater, switch assembly and cover in the assembled position relative to the case.

Embodiments of the Invention A delay relay according to the present invention will be described below with reference to the drawings, and throughout each drawing, corresponding reference numbers indicate corresponding members.

The delay relay unit l-(
TDR) has a case 3 made of a non-conductive material (for example, molded composite or resin), and the case has a housing portion 5 and a pair of terminal receiving grooves γa and 7b molded into the case. It is shown that

Enclosed one-piece thermostat switch assembly 9
is installed in the storage section 5.

The assembly 9 includes a case 11 used to be received within the housing 5 and a pair of electrical contacts 1 mounted within the case.
3a and 13b.

As shown in FIG. 3, the contact 13a is mounted on the support arm 15, and the contact 13b is elastically cantilevered from the side of the switch case 11 and brought into contact or non-contact with the contact 13a. It is fixed to the free end of the contact arm 1γ which is movable within the case so as to move the contact 13b.

Contacts 13a, 13b are normally spring-loaded and closed by arm 17.

Thermostatic element 149 - e.g. U.S. Pat.
A snap-acting bimetallic disc of the type disclosed in US Pat. No. 4,448,240 is mounted within the case 11.

Element 1 cannot be expanded and has a concave shape.
9 moves quickly from one curved state to the opposite curved state in response to a change in temperature, applying a mechanical force to actuate the contact arm 1γ of the switch component 9.

The disc 19 is located within the cup-shaped end 21 of the case 11.
It is attached to the bottom of the case 11.

The end portion 21 is made of a material having good electrical conductivity and good heat transfer properties, such as copper.

The circumference of the disc 19 is supported by an internal shoulder 23 of the cup-shaped end 21.

A tablet-shaped heater 25 is fixed to the lower surface of the cup-shaped end 21 for heat conduction, and this heater constitutes a means for heating the disc 19.

The heater has a steep positive temperature coefficient (referred to as PTC).
materials with a resistivity-temperature curve, such as U.S. Pat.
489.976 and as exemplified.

At a temperature below a predetermined temperature increase, the bimetallic disk has a disk shape with a concave upper surface (see FIG. 3).

When heated, the disk quickly moves past the center and its upper surface becomes convex.

The actuation or transmission pin 26 is axially connected to the cylindrical pin guide 2.
It is possible to slide within the T.

As a result, when the disk 19 moves quickly into the convex upward curve, the pin 26 is moved upward and engages the intermediate round protrusion 28 at both ends of the contact arm 11, thereby , arm 1
7 and open the contacts 13a and 13b.

The pair of terminals 29a and 29b are for supplying electric power to the heater 25, and are provided in the receiving groove γa in the case 3, respectively.
, Tb (one terminal in each groove).

Each terminal 29a, 29b has a contact portion 31a, 31b, and each contact portion extends into the storage portion 5, respectively.

As a result, the contact portion 31a of the terminal 29a engages and makes electrical contact with the central lower surface of the heater 25, and the contact portion 3lb of the terminal 29b engages with the cup-shaped end portion 21 and comes into electrical contact, and both constitutes the other terminal of the heater body 25.

Terminals 29a29b and heater 25 thus form a heater circuit to which electrical power is supplied to energize the heater.

The switch assembly 9 has a pair of terminals 33a and 33b, each terminal being connected to a contact 13a and 13b, respectively.

These terminals and contacts form an electrical circuit that is opened in response to energization of the heater circuit by displacing the disc 19 beyond the center and opening the contacts 13a and 13b.

It is understood that the arrangement of the disc and the contacts is such that the contacts open with increasing temperature.

Terminals 29a, 29b are structurally identical in their upper portions, and both have central portions 35a, 35b and a shoulder portion 39a between the central portion and external terminal portions 37a, 37b.
, 39b, and shoulders 41a, 41b at the bottom of the central part.
and quick connector portions 3γa, 37b.

Each terminal has a tab 43a, 43b protruding from a central portion, the upper free end of the tab extending outwardly from the central portion, and when the terminal is received in the respective terminal receiving groove γa, 7b.
It has tabs 43a and 43b that extend inwardly toward the storage section 5.

As shown in FIG. 3, the contact portion 31a of the terminal 29a is an elongated arm extending into the housing 5 to ensure electrical contact with the lower surface of the heater 25.

The contact portion 31b of the terminal 33b extends into the housing to make electrical contact with the periphery of the cup 21, and has a relatively short contact finger 3lb protruding from the central portion 35b so as to make conductive contact with the end surface of the heater 25. are doing.

Terminals 29a, 29b are preferably constructed of a resilient conductive material, such as a high quality copper electrical alloy.

Contact portions 31a, 3lb are configured to be biased to ensure resilient engagement with heater 25 and cup-shaped end 21, respectively, thereby maintaining good electrical contact therewith.

Since the terminal receiving grooves γa and γb in the case 3 are the same,
Only one groove will be described in detail below.

Each groove has a thin, outletless groove 45 (see FIG. 4) that is parallel to the axis of the housing 5 in the case and receives the central portions 35a and 35b of the respective terminals 29a and 29b inserted into the housing. It is designed to accommodate.

Each groove is provided with an opening between the receptacle and the central receiving groove such that the contact portions 31a, 3lb of the terminals extend from the central receiving groove in the receptacle and, for example, the terminals 29a, 3lb.
In order to prevent the tab 43a from colliding with the tab 43a when the 29b is inserted into the groove Ta, a coupling a41 is provided which extends into the receptacle in the height force direction along the longitudinal force direction of the groove for the central part. .

Each central receiving groove 45 is capable of engaging with shoulders 41a and 4lb at the bottom of the central part of each terminal 29a and 29b, and when each terminal is inserted into each groove 7a and 7b, it is inserted into the case. Position each terminal appropriately.

Stop members, as indicated at 51 in FIG. The assembly can be engaged with the assembly at the assembly position in the housing, i.e., the heater 25 and the cup 21 are appropriately arranged in the case, and the contact portions 31a, 3 of the terminals 29a, 29b are connected to each other.
When installed in a position where it makes electrical contact with lb, case 1
1 positioning will be performed.

As best seen in FIGS. 2 and 4, the storage portion 5 is a hole with a tenon circular cross section without an outlet, and has an inlet 53 with a tenon rectangular cross section.

A cover of insulating material, indicated generally at 55, fits within the entrance 53 of the housing and engages the top surface of the case 11 of the single thermostat switch assembly 9 to secure the assembly within the housing. hold in position.

The cover 55 has an approximately rectangular cross section in a plane,
It is constructed so as to fit snugly into the entrance 53 of the storage section.

The cover has a protrusion 51 that extends from the back surface into the groove 4T.
The protruding portion 5T has central portions 35a and 35b.
and the tabs 43a, 43 of the terminals 29a, 29b.
b engages the free end of the terminal to prevent movement of the end and also to hold the terminal in its installed position within the case.

As shown at 59, the cover 55 has a plurality of fastening projections on its lower surface, and the cover 55 has a plurality of fastening projections on its lower surface, and the cover 55 has a plurality of fastening projections on its lower surface, and the
1 and holds the switch body in its installed position.

The retaining member 61 is configured to be pushed into a locking position in the housing 53 and tightened to hold and lock the cover in place within the case.

The engagement of the cover protrusion 57 with the tabs 43a, 43b and the engagement of the cover protrusion 59 with the switch body 11 of the switch assembly 9 ensure that all components of the delay relay unit are mutually connected. In addition, the case 3 is held by the holding member 61.
against which it is held in its assembled position.

In particular, the retaining member 61 is preferably made of a hard elastic material, for example elastic steel.

The holding member has a tab 63 that is rectangular in plan and extends forward.

The tab 63 is bent upward from the surface of the main part of the holding member, and the length from one tab of the holding member to the other tab is equal to the length of the storage part 53.
It is slightly larger than its internal size.

Thereby, when the holding member is attached, the holding member is pushed into the storage portion.

By properly attaching the holding member 1, the upper surface of the cover 55 comes into contact with the holding member, and the cover is held in its attached position with respect to the case.

The cover 55 is preferably made of an electrically insulating material, such as a thermosetting synthetic resin, to electrically insulate the switch assembly from the holding member.

When the holding member 61 is attached to the storage part 53, the tab 63 of the holding member will interfere with the facing surface of the case at the entrance of the storage part and will not fit or engage. It is deformed and protruded so that

When the tab 63 is bent upward from the main body of the holding member, even if an attempt is made to remove the holding member attached from the entrance of the storage section, the end of the tab will dig into the side wall of the entrance of the storage section, resulting in This is effective in preventing removal of the holding member.

The feature of this self-tightening and self-locking of the holding member is that
To prevent unnecessary changes to a delay relay unit after assembly.

According to the invention, a simpler, faster and less expensive assembly method is achieved by inserting the blind terminal members 29a, 29b into the respective terminal receiving grooves 7a, Tb.

A case 11 enclosing a single thermostat switch assembly 9 with a heater 25 secured to its bottom is then fitted with contact portions 31a, 3lb and the cup-shaped end portion for electrically contacting the heater and cag 19, respectively. It is inserted into the mounting position in the housing 5 together with the heater in the heat transfer station.

The cover 55 then has a protrusion 5 extending into the coupling groove 4γ.
γ, the terminals 29a,
It engages with the tabs 43a and 43b on the switch body 29b, and further engages with the protrusion 59 that is engaged with the switch body 11.

The holding member 61 then holds the storage portion 53 on the cover 55.
The terminals 29a, 2 are pushed into a predetermined position inside the
9b, the switch assembly 9, and the cover 55 are positively tightened to the respective assembled positions with respect to the case 3 (see FIG. 3).

The delay relay unit assembly method of the present invention eliminates the need for adhesively securing the switch assembly to the case, allows all components to be inserted together along a common vertical axis or plane during assembly, and allows the heater Terminals 29a, 29
To provide an assembly unit that eliminates the need for screwing the unit b into a case, has a smaller overall size, and effectively eliminates unnecessary changes (to prevent unnecessary tampering) from being made to the unit after assembly. .

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a delay relay in an embodiment of the present invention;
Fig. 2 is an enlarged plan view of the delay relay shown in Fig. 1, Fig. 3 is a vertical cross-sectional view taken along the line 3-3 in Fig. 2 to show the internal details, and Fig. 4 shows terminals and switches. Enlarged partial top view showing the bottom of the delay relay case before assembly is installed;
5 and 6 are front views showing two terminals. Explanation of symbols, 1... Delay relay, 3...
・Case, 5... Storage section, 7a, 7b...
... Terminal receiving groove, 9 ... Thermostat switch assembly, 11 ... Switch case, 13a
, 13b... Contact, 15... Support arm, 1
γ...Contact arm, 19...Thermostat element, 21...Cup-shaped end, 25...
...Heater 26...Pin, 29a
, 29b...Terminal, 31a, 3lb...
・Contact part, 33a, 33b...Terminal.

Claims (1)

[Claims] 1. An electric heater 25, a thermostat element 19 that operates in response to the electric heater, and the thermostat element 19.
The delay relay is housed in a case 3 having a cover 55, in which switch contacts 13a, 13b operated by the switch contacts 13a, 13b and terminals 33a, 33b connected to the switch contacts to form a switch circuit are housed in a case 3 having a cover 55, A single switch assembly 9 configured by integrally assembling an electric heater 25, a thermostat I [child 19, switch elements 13a, 13b, and terminals 33a, 33b]; and a single switch assembly 9 extending from the bottom of the case 3 toward its open end. A pair of terminal receiving grooves 7 provided on the inner wall of the case to face each other.
a, 7b, and a pair of terminals 29a, 29b accommodated by being inserted into each of the terminal receiving grooves, one end of each terminal being connected to supply power to the electric heater 25, On the other hand, the other end of each terminal has an end portion that protrudes from the case 3 when the delay relay is assembled, and a pair of terminals 29a and 29b are provided with raised pieces 43a and 43b between the one end and the other end. and for contacting and engaging with the cut and raised pieces 43a and 43b provided on each of the terminals, respectively, to fix each of the terminals in the respective terminal receiving grooves and press and fix the cut and raised pieces when the assembly is completed. A cover 55 is provided with a pair of protrusions 57 and is inserted and fitted into the open end of the case 3 to cover the open end, and after the cover 55 is inserted, a cover 55 is provided with a pair of protrusions 57 and a cover 55 is inserted and fitted into the open end of the case 3 to cover the open end. A holding member 61 that is elastically fitted together,
a holding member 61 configured such that the terminals 29a and 29b are pressed and fixed by the cover 55 and the cover 55 is pressed and fixed by the holding member when the assembly is completed; A slow MIJ radar characterized in that it can be assembled by an insertion operation for the switch assembly 9 and the terminals 29a and 29b, and a fitting operation for the cover 55 and the holding member 61.