JP3343476B2 - Image forming device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image forming apparatus, and more particularly, to an image forming apparatus which detects opening and closing of two open / close lids formed on a housing by one switch means.

[0002]

2. Description of the Related Art Generally, in an image forming apparatus such as a facsimile machine, a copying machine, and a laser printer, a recording section for recording an image on a recording sheet, a recording sheet conveying section for conveying the recording sheet to the recording section, and a housing. It has a recording paper discharge unit and the like that conveys and discharges the recording paper on which the image is formed to the recording paper tray outside the housing, and in order to clear the recording paper jam and replace parts in these parts, In the housing of the image forming apparatus,
An opening / closing lid is formed.

In this case, in order to form an image using a high voltage or to convey the recording paper, it is usually detected in the housing of the image forming apparatus that the opening / closing lid is opened. A detection switch for stopping supply of voltage is provided. This detection switch requires only one detection switch when there is one opening / closing lid, but two detection lids are provided in order to remove jams in the housing of the image forming apparatus and to improve workability of component replacement. Traditionally,
In order to detect the opening and closing of each opening / closing lid, two detection switches are provided.

However, when two detection switches are provided,
There is a problem that the cost of the image forming apparatus is increased due to wiring and signal processing corresponding to the number of switches.

Therefore, an image reading and recording apparatus described in Japanese Patent Application Laid-Open No. 2-151169 has been proposed. The image reading and recording apparatus includes a conveying roller for conveying the original, a separating member for separating the original one by one, a reading apparatus for reading the original to be conveyed, and a reading roller for pressing the original against the reading apparatus. And a recording roller configured to convey a recording sheet, and a recording device configured to perform recording on the recording sheet pressed by the recording roller, and a recording system configured to convey the recording sheet. In the image reading / recording apparatus having a path, one of the transport roller and the separating member and one of the reading apparatus and the reading roller are integrally incorporated and are rotated around a rotation center, so that the document is rotated. A document conveying path opening unit for opening a conveying path, and one of the recording roller and the recording apparatus are integrally incorporated and the recording sheet is conveyed by rotating about a rotation center. When the document sheet transport path opening unit is rotated and the document sheet transport path opening unit is not rotated, the latter unit is locked by the former unit, and the recording sheet transport path opening unit is locked. It is characterized by comprising a locking means for limiting the amount of movement, and a detecting means for detecting that the recording sheet transport path opening unit is rotated and stopping the operations of the reading system and the recording system.

According to this image reading and recording apparatus, if the recording sheet transport opening unit cannot be opened, the detecting means for stopping the operation of the reading system and the recording system does not operate, and the recording sheet transport opening unit cannot be opened. When the document transport path opening unit is to be opened, the amount of rotation of the document transport path opening unit is limited by the locking means. By opening the recording sheet conveyance opening unit and detecting that the document conveyance path opening unit has been opened by one detecting means, the safety in case a person enters the inside of the image reading and recording apparatus can be improved. Trying to secure.

[0007]

However, in such a conventional image forming apparatus, if the recording sheet transport opening unit cannot be opened, the detecting means for stopping the operations of the reading system and the recording system does not operate, and the recording is not performed. If an attempt is made to open the original transport path opening unit in a state where the sheet transport opening unit cannot be opened, the recording sheet transport opening unit must be opened because the rotation amount of the original transport path opening unit is limited by the locking means. If the document feed path opening unit cannot be opened widely, a paper jam occurs, and if the document feed path opening unit is opened wide to remove the jammed paper, it is not necessary to open the recording sheet conveyance unit. There is a problem that the open unit must be opened, and the usability of the image forming apparatus is poor.

That is, in an image forming apparatus such as a laser printer, the inside of the main body is opened when a paper transport path is opened for removing jammed paper or the like and when consumables or faulty products are replaced. Recently, image forming apparatuses have been downsized,
The weight has been reduced, and it is difficult to open a sufficient space for exchanging consumables and failed parts by opening only one opening / closing lid. For this purpose, it is necessary to provide two opening / closing lids and open a sufficient space for exchanging parts. In this case, as in the conventional case, one opening / closing lid (opening unit) is used. If the other opening / closing lid must be opened even when it is not necessary to open the image forming apparatus, the usability of the image forming apparatus deteriorates.

Therefore, according to the first aspect of the present invention, there is provided an operating means for directly turning on / off one switch means attached to a housing to two opening / closing lids formed in a housing and forming one opening. And the pressing means for pressing the operating means against the switching means are separately provided, so that any opening / closing lid can be opened and detected by one switching means, the number of parts is reduced, the cost is low, and It is an object of the present invention to provide an image forming apparatus having good usability.

According to a second aspect of the present invention, the switch means and the operating means are further provided with an elastic means for urging the switch means and the operating means in a direction in which they are pressed against each other. It is an object of the present invention to provide an image forming apparatus which can be biased by the above to stabilize the switching operation of the switch means.

According to the third aspect of the present invention, the number of components is further reduced by forming the elastic member for stabilizing the switch operation and the release means for separating the operation means from the switch means by one member, thereby further reducing the number of parts. It is an object to provide an inexpensive image forming apparatus.

[0012]

[0013]

[0014]

According to the first aspect of the present invention, an image forming apparatus records an image on a recording sheet conveyed on a conveying path formed in a housing by a recording unit, and the recording unit performs the recording. In an image forming apparatus which further conveys the recording paper on which an image is recorded through a conveyance path and discharges the recording paper to the outside of the housing, the recording paper is formed on the housing and opened in opposite directions to each other, thereby forming the conveyance path and the recording paper. Two opening / closing lids forming one opening for opening a portion; switch means provided in the housing for ON / OFF operation to detect opening / closing of the opening / closing lid; and one of the opening / closing lids. Operating means for energizing the switch means to perform on / off operation; release means attached to the opening / closing lid to which the operating means is attached, for urging the operating means in a direction away from the switch means; Working hand Attached to the lid different from the lid which is attached with a pressing means for pressing said actuating means to said switch means direction, by providing, have achieved the above objects.

[0015] According to the above construction, the operating means for directly turning on / off one switch means attached to the housing to the two opening / closing lids formed in the housing to form one opening; And the pressing means for pressing the pressing means to the switching means are provided separately, so that any opening / closing lid can be opened, it can be detected by one switching means, the number of parts can be reduced, and the image forming apparatus can be realized. In addition to being inexpensive, the usability of the image forming apparatus can be improved.

In this case, for example, as described in claim 2, the image forming apparatus is provided between the switch means and the operating means, and the operating means is pressed by the pressing means in the switch direction. If so, an elastic means for urging the switch means with a predetermined elastic force may be further provided.

According to the above construction, since the elastic means for urging the switch means and the operating means in the direction of pressing each other is further provided, the switch means can be moved by the elastic means even if the opening / closing lid moves slightly or rattles. Can be energized,
The switching operation of the switching means can be stabilized.

Further, for example, as set forth in claim 3, the operating means is attached to the opening / closing lid so as to be rotatable about a predetermined axis, and the elastic means is a plate having predetermined elasticity. The operating means is attached to the end of the operating means on the switch means side, and the pressing means engages with the end of the operating means on the side opposite to the elastic means to rotate the operating means. The elastic means is pressed against the switch means, and the releasing means contacts a part of the opening / closing lid to which the releasing means is attached by utilizing a part of the elastic means which is the plate-like member. It may be formed so as to extend in a direction in which the switch is brought into contact with the switch, and bias the operation unit in a direction away from the switch unit.

According to the above configuration, since the elastic member for stabilizing the switching operation and the releasing means for separating the operating means from the switching means are formed by one member, the number of parts can be further reduced, and the image can be reduced. The forming apparatus can be made more inexpensive.

[0020]

[0021]

[0022]

[0023]

[0024]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. It should be noted that the embodiments described below are preferred embodiments of the present invention, and therefore, various technically preferable limitations are added. However, the scope of the present invention is not limited to the following description. The embodiments are not limited to these embodiments unless otherwise specified.

FIGS. 1 to 3 show a first embodiment of the image forming apparatus of the present invention. FIG. 1 shows a laser to which the first embodiment of the image forming apparatus of the present invention is applied. FIG. 2 is a side sectional view of the printer 1.

In FIG. 1, a photoreceptor 3 is provided at a substantially central portion on the front side in a main body case 2 of a laser printer 1, and a charging unit 4, a developing unit 5, A transfer unit 6, a cleaning unit 7, and the like are provided.

Below the photoreceptor 3, a paper feed cassette 9 containing a plurality of recording papers 8, a recording paper 8 in the paper feed cassette 9 is provided.
And a registration roller 11 for sending the recording paper 8 conveyed by the paper feed roller 10 to the transfer unit 6 at a predetermined timing, and the like. A fixing unit 12 for heating and fixing the recording paper 8 to which the toner No. 3 has been transferred is provided above the transfer unit 6.

The fixing section 12 conveys the recording paper 8 to a paper discharge roller 13 while performing a fixing process on the recording paper 8, and the paper discharge roller 14 is in contact with the paper discharge roller 13. The paper discharge roller 13 cooperates with the paper discharge roller 14 to discharge and place the recording paper 8 sent from the fixing unit 12 on the stacker unit 15.

That is, the fixing section 12 includes a fixing roller 12a and a pressure roller 12b.
The recording paper 8 to which the toner has been transferred is sent out of the transfer path 6 substantially vertically from the transfer path 6, and is conveyed along the transfer path 18 to the contact portion between the fixing roller 12 a and the pressure roller 12 b.
The fixing unit 12 conveys the recording paper 8 conveyed from the transfer unit 6 while pressing the recording paper 8 against the fixing roller 12a by the pressure roller 12b.
By heating at a, the toner transferred to the recording paper 8 is fixed on the recording paper 8.

A stacker portion 15 for discharging the recording paper 8 on which an image has been formed is formed in the upper portion of the rear side (left side in FIG. 1) of the main body case 2. The main body case 2 below the stacker portion 15 is formed. Inside, an electrical component 16 is provided.
An optical device 17 that writes an image on the photoconductor 3 is provided below the electrical unit 16.

As shown in FIG. 2, a front cover (opening / closing lid) 20 is provided on the front side (right side in FIG. 1) of the main body case 2 so as to be able to open and close a predetermined angle about the shaft 19 in the horizontal direction in FIG. The fixing unit 12 and the transfer unit 6 are attached to the front cover 20. The stacker unit 15
The upper part of the main body case 2 forming a part is formed as a paper discharge cover (opening / closing lid) 21 on the side of the paper discharge roller 13. As shown in (1), it is supported so that it can be opened and closed by a predetermined angle in the left-right direction. Therefore, the laser printer 1 has the front cover 2
1 and 2 can be opened and closed in opposite directions, that is, in the left and right directions in FIGS. 1 and 2. When the front cover 20 and the discharge cover 21 are opened, the conveyance path 18 is centered. By forming an opening whose inside is greatly opened, it is possible to easily remove a recording sheet having a jam and replace consumables such as toner of the developing unit 5.

An interlock switch (switch means) 23 is provided below the stacker section 15 in the main body case 2 on a frame or the like of the main body case 2. The interlock switch 23 has a switch terminal 23 a (see FIG. 2) and a switch lever 23b. The switch lever 23b has one end attached to the interlock switch 23 and its free end connected to the switch terminal 2.
3a. The interlock switch 23 is
When the switch lever 23b is pushed toward the interlock switch 23, the switch lever 23b urges the switch terminal 23a to be turned on. The interlock switch 23 is one of various power supplies of the laser printer 1.
Each unit using a high-voltage power supply, for example, the fixing unit 12 and the transfer unit 6
It is a sensor for controlling the stop and the start of the supply of the high-voltage power to the power supply and the like, and the control unit in the electrical unit 16 controls the supply and the stop of the high-voltage power by the ON / OFF signal of the interlock switch 23.

A switch operating lever (operating means) 24 is disposed below the paper discharge cover 21. The switch operating lever 24 is attached to the paper discharge cover 21 so as to be rotatable about a shaft 24a. ing. As shown in FIG. 3, on the surface of the switch operating lever 24 on the side of the paper output cover 21,
An elastic member (elastic means) 25 that is longer than the switch operating lever 24 by a predetermined amount is fixed, and the elastic member 25 is, for example, a leaf spring or the like. The elastic member 25 has a pressing member (release means) 26 formed by cutting and raising a part of a portion located above the switch operating lever 24 over a predetermined length.
As shown in FIGS. 1 and 2, the leading end of the paper ejection cover 21 contacts the back surface of the paper ejection cover 21 and urges the switch operation lever 24 in a direction for rotating the switch operation lever 24 counterclockwise about the shaft 24a.

The switch operating lever 24 is connected to the discharge cover 2.
When the front cover 1 and the front cover 20 are closed, the leading end thereof is connected to the switch lever 23b of the interlock switch 23.
To the switch terminal 23a side to turn on the interlock switch 23. That is, on the surface of the fixing unit 12 attached to the front cover 20 on the side of the discharge cover 21, an engagement projection (pressing means) 27 that engages with the upper end of the switch operating lever 24 on the side of the fixing unit 12 is provided. When both the paper discharge cover 21 and the front cover 20 are closed, the engagement protrusion 27 is provided.
And the switch actuating lever 24 is engaged with the shaft 2
Rotate clockwise around 4a. When the switch operation lever 24 is rotated clockwise by the engagement protrusion 27,
Elastic member 25 attached to switch operating lever 24
Biases the switch lever 23b, and the switch terminal 23a
Is pressed to turn on the interlock switch 23.

Next, the operation will be described. In the laser printer 1, the front cover 20 and the paper output cover 21 can be opened and closed in opposite directions, that is, in the left and right directions in FIGS.
When one of the front cover 20 and the paper output cover 21 is opened, one interlock switch 23 detects that either the front cover 20 or the paper output cover 21 is opened, and the internal high-voltage power is supplied. There is a feature of where to stop.

That is, the laser printer 1 is used with the front cover 20 and the paper discharge cover 21 closed.
At this time, the engagement protrusion 27 attached to the front cover 20
However, as shown in FIG. 1, the switch operating lever 24 rotatably attached to the paper output cover 21 is engaged with the upper end of the front cover 20 side, and the switch operating lever 24 is rotated clockwise. Energize in the direction to cause. Therefore, the elastic member 25 attached to the switch operating lever 24 urges the switch lever 23b toward the switch terminal 23a,
The interlock switch 23 is turned on. When the interlock switch 23 is turned on, the control unit of the electrical unit 16 of the laser printer 1 determines that the front cover 20 and the paper discharge cover 21 are closed, and the main power of the laser printer 1 is turned on. Supply a high voltage internally.

In this state, in the laser printer 1, the optical device 17 forms an electrostatic latent image on the photosensitive member 3 uniformly charged by the charging section 4 based on the image data, and forms the electrostatic latent image. The developing unit 5 causes toner to adhere to the photosensitive member 3 thus formed, thereby visualizing (developing) the image. The laser printer 1 transfers the toner adhered to the photoreceptor 3 onto the surface of the recording paper 8 conveyed from the paper feed cassette 9 by the transfer unit 6, and places the recording paper 8 with the toner transferred on the conveyance path 18. To the fixing unit 12.

The photoreceptor 3 on which the transfer of the toner image has been completed by the transfer unit 6 has its residual toner removed by the cleaning unit 7 and is charged again by the charging unit 4 to form the next electrostatic latent image. Provided.

The recording paper 8 conveyed to the fixing section 12 is heated by the fixing roller 12a while being in close contact with the fixing roller 12a by the pressure roller 12b, so that the toner on the recording paper 8 is fixed on the recording paper 8 and fixed. The sheet is conveyed to the discharge roller 13 by the rotation of the roller 12a and the pressure roller 12b. The paper discharge roller 13 discharges the recording paper 8 onto the stacker unit 15 in cooperation with the paper discharge roller 14.

In the above-described series of operations, the laser printer 1 generates a jam while the recording paper 8 is being conveyed on the conveyance path 18, and it is necessary to remove the jammed paper, the developing unit 5 runs out of toner, and the toner cartridge In some cases, various parts need to be replaced, such as when replacement is required.

In such a case, if only the jammed paper is to be removed, the jammed paper can be removed by opening only the front cover 20. Therefore, when the front cover 20 is opened, the engagement protrusion 2 attached to the front cover 20 is opened.
7 is separated from the switch operating lever 24, and the switch operating lever 24 is rotated counterclockwise around the shaft 24a by the urging force of the pressing member 26, and the upper portion of the switch operating lever 24 on the front cover side is a paper ejection cover. The rotation of the elastic member 25 is stopped in a state in which the elastic member 25 is in contact with the back surface of the switch 21 and the elastic member 25 is separated from the switch lever 23b. Therefore, the switch lever 23b
Of the switch terminal 23a is released, and the interlock switch 23 is turned off. When the interlock switch 23 is turned off, the control unit of the
When it is determined that the output cover 21 is 0 or the discharge cover 21 is opened, the supply of the high voltage to the internal components is stopped. And in this case,
Since the opening and closing of the front cover 20 is not restricted by the paper discharge cover 21, the front cover 20 is appropriately opened,
Jam paper can be removed.

In the case of replacing various parts, it is necessary to form an opening sufficient for taking in and out of parts.
In this case, as shown in FIG. 2, by opening not only the front cover 20 but also the paper discharge cover 21, it is possible to form an opening sufficient for inserting and removing components. When the front cover 20 and the paper ejection cover 21 are opened, the laser printer 1 separates the engagement protrusion 27 attached to the front cover 20 from the switch operation lever 24 in the same manner as described above. As shown, the urging force of the pressurizing member 26 rotates counterclockwise about the shaft 24a, and the switch actuating lever 24 is rotated in a state where the upper portion on the front cover side is in contact with the back surface of the paper discharge cover 21. Motion stops. Since the switch operation lever 24 is attached to the sheet ejection cover 21, the switch operation lever 24 moves upward together with the sheet ejection cover 21 and the elastic member 25 attached to the switch operation lever 24 is separated from the switch lever 23b. Therefore, the switch terminal 23a by the switch lever 23b
Is released, and the interlock switch 23 is turned off. When the interlock switch 23 is turned off, the control unit of the electrical unit 16 controls the front cover 20 or the paper discharge cover 21.
Is determined to have been opened, and the supply of high voltage to the internal components is stopped.

Thereafter, when the replacement of parts and the like is completed and the front cover 20 and the paper discharge cover 21 are closed, the elastic member 25
Is engaged with the switch lever 23b, and the engagement protrusion 27 attached to the front cover 20 is engaged with the switch operation lever 24, whereby the switch operation lever 24 is rotated clockwise, and the switch lever 23b is turned on. Terminal 2
It is urged to the 3a side.

That is, when the discharge cover 21 is opened, the switch operating lever 24 is urged in the counterclockwise direction by the pressing member 26, so that the upper portion on the front cover side is discharged. The end of the elastic member 25 on the switch lever 23b side has been moved counterclockwise in contact with the back surface of the paper cover 21. As a result, when the paper output cover 21 is closed, the elastic member 25 is properly engaged with the lower end of the switch lever 23b, and the engagement end 27 is engaged with the switch operation lever 24, and the switch operation lever 24 is closed.
Is rotated clockwise, the elastic member 25 urges the switch lever 23b against the switch terminal 23a,
The interlock switch 23 is turned on.

Therefore, as in the prior art, the front cover 20
When one of the front cover 20 and the discharge cover 21 is opened, the opening degree can be properly controlled without restricting the degree of opening, and one interlock switch 23 can be used to open either the front cover 20 or the discharge cover 21. In this case, it is possible to detect that the laser printer 1 is opened, to reduce the cost of the laser printer 1, to improve the workability of work such as removal of jammed paper and replacement of parts, and to improve work safety. Can be secured.

The elastic member 25 engaged with the switch lever 23b of the interlock switch 23 has a predetermined elasticity, and is slightly elastically deformed even after the switch lever 23b is pushed to the switch terminal 23a side. so,
Since the interlock switch 23 is turned on, even if the front cover 20 and the paper output cover 21 slightly move or rattle, it can be absorbed by the elasticity of the elastic member 25. Can be appropriately turned on. As a result, a stable switch operation can be performed, and safety can be improved.

Further, when the discharge cover 21 is opened,
Since the switch operating lever 24 is rotated counterclockwise by the pressing member, the elastic member 25 properly engages with the lower end of the switch lever 23b when the discharge cover 21 is closed. , The interlock switch 23 can be operated properly. As a result, the operation of the interlock switch 23 can be stabilized.

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

Although the invention made by the inventor has been specifically described based on the preferred embodiments, the invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the invention. It goes without saying that it is possible.

For example, in each of the above-described embodiments, the case where the present invention is applied to a laser printer has been described. However, the image forming apparatus is not limited to the laser printer. Equipped with two opening and closing parts that open, for removing jammed paper and replacing parts, etc.
The present invention can be applied to general image forming apparatuses that need to open the opening / closing section.

[0056]

According to the image forming apparatus of the present invention, one switch means attached to the housing is directly connected to two opening / closing lids formed in the housing to form one opening. Since the operating means for turning on / off and the pressing means for pressing the operating means against the switch means are separately provided, even if any of the open / close lids is opened, it can be detected by one switch means. By reducing the number of points, the image forming apparatus can be made inexpensive,
The usability of the image forming apparatus can be improved.

According to the image forming apparatus of the second aspect of the present invention, since the elastic means for urging the switch means and the operating means in the direction of pressing each other is further provided, the opening / closing lid slightly moves or rattles. Also, the switch means can be urged by the elastic means, and the switching operation of the switch means can be stabilized.

According to the image forming apparatus of the third aspect of the present invention, the elastic member for stabilizing the switching operation and the releasing means for separating the operating means from the switching means are formed by one member, so that the number of parts can be reduced. Further reduction can be achieved, and the image forming apparatus can be made more inexpensive.

[0059]

[0060]

[Brief description of the drawings]

FIG. 1 is a side sectional view of a laser printer to which an image forming apparatus according to a first embodiment of the present invention is applied.

FIG. 2 is a side sectional view of the laser printer of FIG. 1 in a state where a front cover and a paper discharge cover are opened.

FIG. 3 is an enlarged perspective view of a switch operating lever and an elastic member of FIG. 1;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 laser printer 2 main body case 3 photoreceptor 4 charging unit 5 developing unit 6 transfer unit 7 cleaning unit 8 recording paper 9 paper feed cassette 10 paper feed roller 11 registration roller 12 fixing unit 12a fixing roller 12b pressure roller 13 paper discharge roller 14 Discharge roller 15 Stacker section 16 Electrical section 17 Optical device 18 Transport path 19 Axis 20 Front cover 21 Discharge cover 22 Axis 23 Interlock switch 23a Switch terminal 23b Switch lever 24 Switch operating lever 24a Axis 25 Elastic member 26 Pressurizing member

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) G03G 15/00 550 G03G 21/16-21/18 B41J 29/00-29/70

Claims (3)

(57) [Claims] An image is recorded on a recording sheet conveyed on a conveying path formed in a housing by a recording section, and the recording sheet on which the image is recorded by the recording section is further conveyed on a conveying path. In the image forming apparatus for discharging to the outside of the housing, two opening / closing lids formed on the housing and opened in opposite directions to form one opening for opening the transport path and the recording unit. Switch means provided on the housing to detect opening / closing of the open / close lid by performing on / off operation; and operating means attached to one of the open / close lids to bias the switch means to perform on / off operation. Release means attached to the opening / closing lid to which the operating means is attached, for urging the operating means in a direction away from the switch means; and detaching the opening / closing lid different from the opening / closing lid to which the operating means is attached. Vignetting, image forming apparatus, characterized in that said operation means has and a pressing means for pressing the switch unit direction. 2. The image forming apparatus is provided between the switch means and the operating means, and when the operating means is pressed in the switch direction by the pressing means, the switch means is pressed by a predetermined elastic force. 2. The image forming apparatus according to claim 1, further comprising an elastic unit for urging. 3. The operating means is attached to the opening / closing lid so as to be rotatable about a predetermined axis, and the elastic means is formed of a plate-like member having predetermined elasticity. The pressing means is attached to an end on the switch means side, and the pressing means is engaged with an end of the operating means on the side opposite to the elastic means to rotate the operating means, thereby causing the elastic means to switch the elastic means to the switch means. Press, the release means is formed to extend in the direction of contacting a part of the opening and closing lid attached to the release means using a part of the elastic means which is the plate-shaped member, 3. The image forming apparatus according to claim 2, wherein the operation unit is urged in a direction away from the switch unit.