JPS63318038A - Timer device - Google Patents

Abstract

PURPOSE:To prevent the unbalanced load and smoothly perform the rotation of an operating shaft by arranging the switch operating face of a control cam and the switch operating face of a mode judging cam at positions pinching the operating shaft from both sides in the radial direction. CONSTITUTION:The switch operating faces 61 of cams are arranged at positions pinching the operating shaft 12 from both sides in the radial direction. Forces applied to the operating shaft 12 through the cams are offset and balanced on this operating shaft 12, the unbalanced load from one side in the radial direction is not applied to this operating shaft 12 although multiple cams 42, 47, 48 are provided on the same operating shaft 12. The load on the bearing portion of the operating shaft 12 is thereby reduced, the unbalanced abrasion at the bearing portion can be prevented, end the rotation of the operating shaft 12 is made smooth.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a timer device used in a cooking appliance such as a toaster oven.

[Conventional technology]

The toaster oven has a built-in mechanical timer that determines the amount of time the heater is energized depending on the food being cooked.The toaster oven has an escape wheel that interlocks with the operation shaft, and a balance that is removably engaged with the escape wheel. When the timer knob is grasped and the operating shaft is rotated, the mainspring is wound up by an amount corresponding to the amount of rotation, thereby setting the timer operating time. When the balance wheel operates in conjunction with this winding, the operating shaft is rotated in the rewinding direction by the return force of the mainspring, and the timer operation is started.

[Problem to be solved by the invention]

However, since conventional mechanical timers are operated by the restoring force of a mainspring, their operating speed is constant over the entire operating time, and the scale indicating the timer time is spaced at equal intervals in the rotation direction of the operating shaft. It was attached to.

For this reason, as the total operating time of the timer increases, the interval between each scale becomes narrower, and the scale becomes too fine, making it difficult to set the timer operating time, and the setting error also increases, which increases the cooking time. There are problems with excess and shortage.

On the other hand, if the interval between each scale is increased, the number of scales and the total operating time will be shortened due to space issues, resulting in a significant restriction on the cooking time.

Furthermore, in recent years, timers using microcomputers have been developed in place of this type of mechanical timer.

However, since this timer uses an LED or the like to perform digital display, there is a problem in that the peripheral circuitry described above for counting EDs is costly and the timer itself becomes expensive. Moreover, compared to the conventional analog display in which the timer knob is adjusted to the scale, setting the timer time requires more effort and is difficult to use.

Therefore, the present invention makes it possible to accurately and easily set the timer time during frequently used hours, and also prevents unbalanced loads from being applied to the operating shaft, allowing smooth rotation of the operating shaft. Another object of the present invention is to provide a timer device in which switches can be easily arranged in a limited space around the operating shaft.

[Means to solve the problem]

Therefore, the timer device of the present invention that achieves the above object has an operating shaft that is rotatably operated, a scale that displays time and is provided at intervals in the direction of rotation of the operating shaft, and comprising a drive means for rotating in a direction opposite to the winding direction, and a control means having a plurality of modes for changing the drive speed of the drive means in stages according to the rotation angle of the operating shaft, The operating shaft is rotatably supported on the frame, and on this operating shaft, a control cam that opens and closes the control switch of the driving means, and a mode discrimination cam that opens and closes the changeover switch that switches between the plurality of modes are mounted on the operating shaft in the axial direction. The switch operating surface of the control cam and the switch operating surface of the mode discrimination cam are arranged at a position where they sandwich the operating shaft from both sides in the radial direction.

[Effect]

According to this configuration, when the operating axis is set in a time period when the timer is used frequently, if the driving means is controlled so that the driving speed of this operating axis becomes faster, the scale in the above time period will be adjusted accordingly. It is possible to partially set the interval to be wider than the scale interval for other time periods. Therefore, setting the timer time during a frequently used time period can be easily and accurately performed.

Moreover, by arranging the switch operation surface of each cam at a position where the operating shaft is sandwiched from both sides in the radial direction, the forces applied to the operating shaft through each cam can cancel each other out and be balanced on this operating shaft. Therefore, even though a plurality of cams are provided on the same operating shaft, an unbalanced load from the blade side in the radial direction is not applied to the operating shaft.

This reduces the burden on the bearing part of the operating shaft, prevents uneven wear of the bearing part, and allows smooth rotation of the operating shaft, ensuring reliable operation of the drive means and control means by the cam. becomes.

Additionally, the switches that are opened and closed by cams are distributed on both sides of the operating shaft in the radial direction, making it possible to compactly arrange the switches in a narrow space around the operating shaft without increasing the spacing between the cams. can.

- [Example] An example of the present invention will be described below based on drawings in which the present invention is applied to a toaster oven.

9. Middle tube number 1 in Figure 9 is a case that constitutes the outer shell of the toaster oven, and the front panel 2 of this case 1 has an opening/closing door 3.
is rotatably mounted.

A cooking chamber 5 that can be opened and closed by an opening/closing door 3 is formed in the case 1, and a heater 6 for cooking is provided in this cooking chamber 5. This heater 6 is connected to a commercial AC power source 7 via a plug 1a.

A timer storage chamber 8 is formed in the case 1 and is separated from the cooking chamber 5. A timer device 9 for controlling the time period during which the heater 6 is energized is provided within the timer storage chamber 8. As shown in FIGS. 1 and 2, this timer device 9 has a box-shaped frame 10. A bracket 11 is attached to the front surface 10a of the frame 10, and this bracket 11 is screwed to the back surface of the front panel 2.

An operating shaft 12 is rotatably supported on the upper part of the frame 10. This operating shaft 10 rotatably passes through a through hole 10c provided in the frame 1o, and one end of this operating shaft 12 passes through the front panel 2 and is led out. A timer knob 4 is attached to the leading end of the operating shaft 12, and the operating shaft 12 is artificially rotated together with the timer knob 4 in the timer winding direction and rewinding direction. When the operating shaft 12 is rotated in the timer winding direction, a mainspring (not shown) is wound up in conjunction with this, and the return force of this mainspring causes the operating shaft 12 to be rotated in the timer winding direction (in the direction of arrow A in FIG. 6). ) is biased to rotate.

In addition, the operating shaft 12 has a large gear j3 that rotates integrally with the operating shaft 12.
is being taken away. The large gear 13 meshes with a pinion 14 that is pivotally supported on the frame 1°, and an escape wheel 15 is coaxially fixed to one end surface of the pinion 14. A balance wheel 16 is arranged below. The balance 16 is rotatably supported on the frame 10 via a pivot 17, and the balance 16 can be engaged with and detached from the teeth 18 of the escape wheel 15 at three points spaced apart in the circumferential direction. A pair of engaging claws 19a and 19b that engage with
is provided.

A bracket 20 is provided at the bottom of the rear surface 10b of the frame 10.
A solenoid 21 is attached to rotate the balance wheel 16 via the solenoid 21. The solenoid 21 converts the alternating current from the commercial alternating current power supply 7 into direct current, and is connected to a stabilized solenoid power supply 23 that adjusts the voltage. It has become. Further, one end of a metal plate 25 is swingably locked to the bracket 20 so as to be spaced apart from and opposite to the iron core 24 . The other end of the metal plate 25 passes through a through hole 26 provided in the rear surface 10b of the frame 10 and extends toward the balance wheel 16.
The locking portion 27 provided at the other end is the locking arm portion 3 of the balance wheel 16.
It's stuck on 1. The metal plate 25 is always urged in a direction away from the iron core 24 by a tension coil spring 28, and this force causes the locking portion 2 of the metal plate 25 to
7 is pushed up, and the balance wheel 16 is urged to rotate counterclockwise as shown by arrow B in FIG. Therefore, among the engaging claws 19a and 19b of the balance wheel 16,
One of the locking pawls 19a located on the rear side in the rotational direction of the escape wheel 15 is locked with the teeth 18 to prevent rotation of the escape wheel 15 due to the return force of the mainspring.

Further, when the metal plate 25 is attracted with the excitation of the iron core 24, the locking portion 27 of the metal plate 25 is pulled down as shown in FIG. 7, and the balance wheel 16 is moved as shown by arrow C in FIG. is rotated clockwise. Then, one of the locking claws 19a that was locked to the escape wheel 15
The escape wheel 15 is no longer restricted from rotating, but
Conversely, the other locking claw portion 19b enters between the teeth 18 of the escape wheel 15. Therefore, when the escape wheel 15 rotates by a certain angle due to the release of the rotation restriction, the other tooth portion 18 locks with the locking pawl portion 19b and prevents the escape wheel 15 from rotating again. It becomes = 9 - becomes.

That is, the escape wheel 15 rotates by one pitch of the toothed portion 18 each time the balance wheel 16 rotates once, and this rotation is transmitted to the operating shaft 1 via the small gear 14 and the large gear 13.
2, the operating shaft 12 is intermittently rotated in response to the excitation of the solenoid 21. Therefore, in this embodiment, the escape wheel 15, the balance wheel 16° metal plate 25, and the solenoid 21 constitute a driving means 29 for driving the operating shaft 12.

Furthermore, on the front panel 2 of the case 1, there is a scale 30 located around the timer knob 4 that displays the energization (cooking) time in 1-minute increments up to 30 minutes. By aligning the index projections 4a of No. 4, the timer time is set.

On the other hand, on the rear surface 10b of the frame 10, when the timer knob 4 is rotated from the off position to the timer winding direction, the heater 6 is energized and the solenoid stabilized power supply 2 is provided.
a control switch 40 for operating the drive means 29 via 3;
is provided. The control switch 40 is a normally open microswitch, and is located below the operating lever 12, and its push button 41 is opened and closed in conjunction with the rotation of the operating shaft 12.

To explain this interlocking structure, a disk-shaped control cam 42 is fixed to the outer periphery of the end of the operating shaft 12 on the opposite side from the timer knob 4. A cam driven plate 43 is provided. The cam follower plate 43 is attached to the frame 10 as shown in FIG.
It is rotatably supported on the rear surface 10b via a pivot 44, and the pin 45 of this cam driven plate 43 is rotated from below the operating shaft 12 against the cam surface 42a formed on the outer peripheral edge of the control cam 42. are in contact with each other. In addition, the cam driven plate 4
A pressing tongue piece 46 is formed at the end opposite to the pivot portion of 3, and a control switch 4 is mounted on the lower surface of this pressing tongue piece 46.
0 push button 41 is in contact with it. The push button 41 is always projected upward, and the cam follower plate 43 is connected to the pivot 4.
The pin 45 of the cam follower plate 43 is pressed against the cam surface 42a.

Therefore, when the operating shaft 12 is rotated in the winding direction via the timer knob 4, the cam driven plate 43 is rotated downward according to the shape of the cam surface 42a, the control switch 40 is closed, and the heater 6 And the solenoid 21 is energized.

By the way, such a timer device 9 includes a microcomputer 35 that controls the energization of the solenoid 21, as shown in FIG. The microcomputer 35 is driven by a microcomputer stabilized power supply 36 that converts the alternating current from the commercial AC power supply 7 into direct current and adjusts the voltage. When set to a short period of 15 minutes from the cut position, timer knob 4 is set once every 30 seconds, and timer knob 4 is set for 15 minutes to 30 minutes.
When set to a long period of up to 1 minute, a program is set up to send an operating pulse to the solenoid 21 at a rate of once per minute.

Therefore, when the timer knob 4 is set to the short time period, the energization interval to the solenoid 21, that is, the de-energization interval from one energization time to the next energization time, is 30 seconds, and conversely, when the timer knob 4 is set to the long time period, The de-energization interval is one minute, and the energization of the solenoid 21 is controlled in these two types of drive modes.

Note that tube number 37 in FIG. 8 is a microcomputer 35.
an oscillation circuit that oscillates a pulse that serves as a time reference; 3
8 indicates a buzzer that notifies completion of the timer operation.

Further, on the operating shaft 12, adjacent to the control cam 42,
A pair of disk-shaped mode discrimination cams 47, 48 are fixed at an interval in the axial direction. A normally open enlargement switch 49 and a normal switch 50 for switching the drive mode of the microcomputer 35 are provided above the mode discrimination cams 47 and 48. Operators 49a of these switches 49,50.

50a is in contact with cam surfaces 47a, 48a formed on the outer peripheral edge of the mode discrimination cam 47, 48, and contacts 60 (switch operation surface) of these cam surfaces 47a, 48a with the operators 49a, 50a, The contact point 61 (switch operation surface) of the cam surface 42a with the pin 45 is the contact point 61 of the cam surface 42a with the pin 45
For example, the operating shaft 12 is disposed at a position offset by 180° in the circumferential direction of the shaft 12, that is, in a positional relationship such that the operating shaft 12 is sandwiched between the operating shaft 12 from both sides in the radial direction.

Then, when the operating shaft 12 is rotated in the winding direction via the timer knob 4, the operating members 49a and 50a are pushed up according to the shapes of the cam surfaces 47a and 48a.
Each switch 49,50 is adapted to be closed individually. That is, in the case of this embodiment, when the indicator protrusion 4a of the timer knob 4 is in the off position, it closes when the timer knob 4 is set to the short time period, and the normal switch 5
0 is designed to close when the indicator protrusion 4a is set for a long period of time from 15 minutes to 30 minutes.

Therefore, these switches 49 and 50 cause the operation shaft 1 to
The rotation angle of 2, that is, the set timer time is detected, and the drive mode of the microcomputer 35 is set to a first mode in which operating pulses are sent to the solenoid 21 at 30 second intervals, or a second mode in which operating pulses are sent out at 1 minute intervals. The drive mode can be switched to one of two drive modes.

At the same time, when the timer time is set to a short time period in this way, the microcomputer 35 outputs 30
The operating pulse is sent out at a rate of once per second, and the driving speed of the drive mechanism 29 is twice that of when it is set for a long time period, so the short time period is set as shown in Fig. 5. The interval L1 between the scales 30 to be displayed is expanded to twice the interval L2 between the scales 30 in the long period.

Furthermore, a wiring board 51 made of an electrically insulating material is attached to the front surface 10a of the frame 10 to support the microcomputer 35 and various electrical circuit components (not shown). The wiring board 51 is attached to the frame 10 as shown in FIG.
The wiring board 51 itself forms a part of the frame 10. The wiring board 51 faces the rear surface 10b and covers the metal plate 25 and the through hole 26 from the front.

Furthermore, a toast switch 52 dedicated to baking bread is provided on the front surface of the wiring board 51. toast switch 52
The leading end of the frame 10 passes through the rear surface 10b of the frame 10, and a cam surface 53 provided at this penetrating end engages the cam driven plate 4.
It is in contact with an arm portion 54 extending downward from 3. When the toast switch 52 is pushed in against the biasing force of the return spring 55, the cam surface 53 contacts the arm portion 54 and pushes down the arm portion 54, similar to when the operating shaft 12 is rotated in the winding direction. , cam driven plate 48
The control switch 40 is closed by rotating the switch downward.

When the control switch 40 is closed, the heater 6 and the solenoid 21 are energized as described above, so the metal plate 25 is attracted and the cam driven plate 43 is held in a downwardly rotated state. , control switch 40
remains closed. Moreover, when the toast switch 52 is operated, the microcomputer 35 sets the timer time exclusively for bread baking without the need to operate the timer knob 4.

Further, on the front side of the wiring board 51, there is a cancel switch 56 for canceling bread baking, a slide switch 57 for adjusting the browning color, and a timer knob 4 that turn on when turned up or when the toast switch 52 is operated. Each of these switches 52, 513, 57 and the indicator lamp 58 is
It is exposed on the front panel 2 together with the timer knob 4.

The front panel 2 is provided with a changeover switch 59 for changing the wattage of the heater 6 into three levels: "strong,""medium," and "weak."

According to such a configuration, the indicator protrusion 4a of the timer knob 4
Since the microcomputer 35 sends operating pulses to the solenoid 21 at 30 second or 1 minute intervals depending on the set position of the solenoid 21, the solenoid 21 is intermittently energized and Rotate. Then, each time the balance wheel 16 rotates once, the escape wheel 1
5 rotates by one pitch of the tooth portion 18 due to the restoring force of the mainspring, and the timer operation is started.

When the timer operation is completed by rotating the index protrusion 4a to the off position, the enlargement switch 49, normal switch 50, and control switch 40 are opened, and the power supply to the heater 6 and solenoid 21 is cut off. When the process is completed, this completion is notified by the buzzer 38 sounding.

By the way, when you set the timer time to a short time period,
The solenoid 21 is excited at half the time interval when set for the long time period, and the drive speed of the operating shaft 12 doubles after 15 minutes, so the scale 30 of the short time period is energized by that amount.
The interval L1 can be expanded. Therefore, even though the total operating time of the timer is relatively long at 30 minutes and the number of scales 30 is large, it is possible to accurately and easily set the timer time in a short period of time that is frequently used. Can be done.

At the same time, the timer time is displayed in an analog manner by setting the indicator protrusion 4a of the timer knob 4 to the desired scale 30, so the setting work can be done in the same way as with conventional mechanical timers. . For this reason,
It does not require any troublesome setup work and has the advantage of being easy to use.

In addition, the control cam 42 and mode discrimination cams 47 and 48 -
In 18=, the push button 41 and the operators 49a and 50a are pressed. Therefore, the above cam 42.4 is attached to the operating shaft]2.
In the above configuration, an external force directed inward in the radial direction is applied via the mode discriminating cam 47°4.
Contact points with the operators 49a and 50a of 8 and the control cam 4
2 and the push button 41 are provided so as to be offset by 180° in the circumferential direction of the operating shaft 12, and are arranged in a positional relationship such that the operating shaft 12 is sandwiched from both sides in the radial direction. The external forces applied to the operating shaft 12 through the cams 42, 47, 48 will cancel each other out and be balanced on this operating shaft 12.

Therefore, a plurality of cams 42° 47 are mounted on the same operating shaft 12.
, 48, the operating shaft 12 has a radial direction of -
There is no need to apply an unbalanced load from the blade side, the load burden on the bearing part of the operation shaft 2 is reduced, and uneven wear of the bearing part can also be prevented. From this, the operation axis 12
The rotation of the solenoid 21 becomes smooth, and the cams 42, 47, and 48 can reliably excite the solenoid 21 and switch modes.

Moreover, since the control switch 40, the enlargement switch 49, and the normal switch 50 are arranged in a distributed manner on both the upper and lower sides of the operating shaft 12, which are spaced apart in the radial direction, the three cams 4 and
A plurality of switches 40, 49, 50 can be compactly arranged in a limited space around the operating shaft 12 without increasing the arrangement interval of switches 2, 47, 48. Therefore, the parts can be placed easily and it is convenient for the part placement.

In addition, in the embodiment described above, the drive speed of the operating shaft was changed in two steps in two drive modes.
For example, if the total operating time of the timer is longer, the operating shaft may be driven in three or more modes.

〔Effect of the invention〕

According to the present invention described in detail above, the driving speed of the operating shaft can be set quickly according to the time period when use is frequently performed.
The scale interval in this time period can be made larger than in other time periods, and the timer time can be set easily and accurately in a frequently used time period.

At the same time, the external forces transmitted to the operating shaft through each cam are canceled out on this operating shaft, so the same operating shaft is used.
Even though a plurality of cams are provided, no unbalanced load is applied to this operating shaft. Therefore, the load on the bearing part of the operating shaft is reduced, and uneven wear of this bearing part can also be prevented, and the rotation of the operating shaft becomes smooth, allowing the drive means and control means by the cam to operate. becomes certain.

Moreover, since the control switches and changeover switches are distributed on both sides of the operating shaft, which are separated in the radial direction, multiple It has the advantage that the switches can be arranged compactly, and it is convenient to arrange the parts easily.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; FIG. 1 is a cross-sectional view of the timer device, FIG. 2 is a view taken from the direction of the arrow in FIG. 1, and FIG. 3 is a front view of the operating part of the timer device. Figure 4 is a sectional view of the part where the timer device is incorporated into the toaster oven, Figure 5 is an operation explanatory diagram showing the operation of the timer knob and the movement mechanism, Figure 8 is a block diagram, and Figure 9 is the toaster oven. FIG. DESCRIPTION OF SYMBOLS 10... Frame, 12... Operation axis, 29... Drive means, 30... Scale, 35... Control means, 40...
...Control switch, 42...Control cam, 47.48.
... Mode discrimination cam, 49.50... Changeover switch (enlargement switch, normal switch), 60.81.
...Switch operation surface (contact). Applicant's agent Patent attorney Takehiko Suzue-22=

Claims (1)

[Claims] an operating shaft that is rotated; a scale that displays time and is spaced apart in the rotational direction of the operating shaft; and a drive means that rotates the operating shaft in a direction opposite to the winding direction; control means having a plurality of modes for changing the drive speed of the drive means in stages according to the rotation angle of the operating shaft, the operating shaft being rotatably supported on a frame; A control cam that opens and closes the control switch of the drive means and a mode discrimination cam that opens and closes the changeover switch that switches between the plurality of modes are provided on this operation shaft at intervals in the axial direction, and the switch operation of this control cam is provided. A timer device characterized in that a switch operation surface of the mode discrimination cam is placed at a position where the operation shaft is sandwiched from both sides in the radial direction.