TWI439791B - Projector lens cover opening and closing device - Google Patents

Description

Projector lens cover opening and closing device

The present invention relates to a projector, and more particularly to a lens cover opening and closing device for a projector.

With the advancement of imaging technology, projectors are widely used in newsletters, conferences, educational training or film and television entertainment, and gradually become the video equipment commonly used by modern people. The projector mainly uses a lens to project image information onto an image surface. If the lens is scratched or contaminated with dust, it will affect the image quality when projecting. Therefore, general projectors are equipped with a lens cover to protect the lens from scratches or dirt. However, since the lens cover is exposed on the outside of the projector, and the lens cover needs to be manually removed before use, the lens cover is easily lost and lost, causing trouble to the user.

In order to improve the above shortcomings, there is a known electric lens cover, such as the Republic of China Announcement No. 512255, which uses the opening and closing of the power source to control the stepping motor drive gear and the rack structure to drive the lens cover to open and close. And can avoid the loss of the lens cover. However, the above-described electric lens cap is not only complicated in construction but also difficult to maintain, and requires extra power to drive the motor to operate. In addition, the lens cover is electrically operated to open and close. If the user does not cover the lens cover, the projector must be powered on again to cover the lens cover, which affects the convenience of the user.

In view of this, the main object of the present invention is to provide a lens cover opening and closing device for a projector, which can automatically control the opening and closing of the lens cover without using an additional power source.

In order to achieve the above object, the present invention provides a lens cover opening and closing device for a projector, the projector having a heat source, a lens and a lens cover, wherein the heat source is used when the projector is started. Generating an image beam and thermal energy; the lens is used to project the image beam onto an imaging surface; the lens cover is reciprocable between a first position shielding the lens and a second position away from the lens The lens cover opening and closing device comprises a driving device connected to the lens cover and having a thermal deformation member located at a position capable of receiving thermal energy generated by the heat generating source for receiving the heat After the thermal energy generated by the light source, deformation occurs to cause the driving device to move the lens cover from the first position to the second position.

According to the above concept, the lens cover opening and closing device of the present invention further includes a returning device coupled to the lens cover for providing a force when the projector is closed, thereby driving the lens cover to move from the second position. To the first position.

In order that the present invention may be more clearly described, the preferred embodiments are illustrated in the accompanying drawings.

Please refer to FIG. 1 , which illustrates a projector 100 according to a first preferred embodiment of the present invention. The projector 100 includes a heat generating light source 110 , a lens 120 , a lens cover 130 , and a lens cover opening and closing device 1 . The heat source 110 is configured to generate an image beam and thermal energy when the projector 100 is activated. The lens 120 is used to project the aforementioned image beam onto an imaging surface (not shown). The lens cover 130 is used to shield the lens 120 when the projector 100 is closed. In addition, since the heat source 110, the lens 120, and the lens cover 130 are all well-known in the art, the principle and detailed structure thereof are not described herein again.

The lens cover opening and closing device 1 has a driving device 10, and the driving device 10 includes a thermal deformation member 11, an amplifying mechanism 12, and a transmission mechanism 13.

The heat deforming member 11 is a wire body made of a unidirectional shape memory alloy (SMA), but is not limited thereto. The heat deforming member 11 is located near the heat generating light source 110 to receive the heat energy generated by the heat generating light source 110. The heat deforming member 11 will be deformed after receiving the heat energy generated by the heat generating light source 110. Of course, in design, the heat deforming member 11 can also use the length change, the thickness change or other type change to achieve the effect of generating the moving force in addition to the shape change.

The amplifying mechanism 12 includes a first lever 121 and a second lever 122, and the first lever 121 and the second lever 122 are both a first type of lever. One end of the first lever 121 is connected to the thermal deformation member 11 , and the other end is connected to one end of the second lever 122 . The fulcrum 121 a of the first lever 121 is located on the first lever 121 and is adjacent to the thermal deformation member 11 . One end. The fulcrum 122a of the second lever 122 is located on the second lever 122 and is close to one end of the first lever 121, so that the other end of the second lever forms an active end with a movement amount larger than the deformation amount of the thermal deformation member.

The transmission mechanism 13 includes a flexible wire body 131 and a plurality of rollers 132. The flexible wire body 131 is disposed along the roller 132 and connects the other end of the second lever 122 and the lens cover 130. Thereby, when the projector 100 is activated, the heat energy generated by the heat generating source 110 will cause the heat deforming member 11 to be deformed, and the first lever 121 and the second lever 122 are actuated, and the second lever 122 is activated. The action end will drive the flexible wire body 131 to drive the lens cover 130 to move from the first position P1 shielding the lens 120 to a second position P2 away from the lens 120, thereby achieving the purpose of opening the lens cover 130. .

In addition, in addition to the amplifying mechanism 12 used in the above embodiment, an amplifying mechanism 14 as shown in FIG. 2 may be used. The amplifying mechanism 14 includes a fixed rotating shaft 141, a wheel body 142 disposed on the rotating shaft, and a a flexible wire body 143; the wheel body 142 has a first circumferential surface 142a and a second circumferential surface 142b centered on the rotating shaft 141, and the circumference of the second circumferential surface 142b is larger than the first circumferential surface 142a One end of the flexible wire body 143 is connected to the heat deforming member 11 and the other end is connected to the first wheel surface 142a; one end of the flexible wire body 131 of the transmission mechanism 13 is connected thereto. On the second wheel surface 142b. Therefore, when the heat deforming member 11 is deformed, the wheel body 142 is rotated by the flexible wire body 143, and the flexible wire body 131 is driven to drive the lens cover 130 to move from the first position P2. Up to the second position P1, the purpose of opening the lens cover 130 is achieved. Of course, in design, in addition to the above-mentioned structure, it is also possible to achieve the same purpose by using only a single lever or using other conventional structural cooperation such as a gear, a sprocket, and the like.

In addition, it should be noted that as long as the length of the thermal deformation member 11 is long enough, the amount of deformation during deformation may be sufficient to drive the lens cover 130 to move from the first position P1 to the second position P2. The lens cover opening and closing device 1 can also achieve the purpose of opening the lens cover 130 without passing through the above-mentioned amplification mechanisms.

It is worth mentioning that, in order to close the projector 100, the lens cover 130 can re-mask the lens 120. The lens cover opening and closing device 1 further includes a returning device 20, a spring, and the lens cover 130. A fixture (not shown) is coupled to provide a force to the lens cover 130. After the projector 100 is closed, the lens cover 130 is moved from the second position P2 back to the first position P1. Of course, in addition to the use of springs, it is also possible to achieve the same purpose by using elastic rubber or magnetic magnetism.

In addition to using the above-mentioned recovery device 20, a heat-deformable member made of a bidirectional shape memory alloy material can be used instead of the function of the recovery device 20, that is, when the projector 100 is activated, the thermal deformation member is heated. Deformed from a first shape to a second shape, thereby driving the lens cover 130 to move from the first position P1 to the second position P2; and after the projector 100 is closed, the heat deforming member is gradually cooled by the second When the shape is deformed back to the first shape, the lens cover 130 is moved from the second position P2 back to the first position P1, thereby achieving the purpose of automatically opening and closing the lens cover 130.

In summary, as described above, the lens cover opening and closing device 1 of the present invention not only automatically controls the opening and closing of the lens cover, but also does not require an additional power source.

The above description is only for the preferred embodiments of the present invention, and the equivalent structures and manufacturing methods of the present invention and the scope of the patent application are intended to be included in the scope of the present invention.

1. . . Lens cover opening and closing device

10. . . Drive unit

11. . . Thermal deformation

12. . . Amplifying mechanism

121. . . First lever

121a. . . Pivot

122. . . Second lever

122a. . . Pivot

13. . . Transmission mechanism

131. . . Flexible wire body

132. . . Wheel

14. . . Amplifying mechanism

141. . . Rotating shaft

142. . . Wheel body

142a. . . First tread

142b. . . Second tread

143. . . Flexible wire body

20. . . Recovery device

100. . . Projector

110. . . Heat source

120. . . Lens

130. . . lens cap

P1. . . First position

P2. . . Second position

1 is a schematic view of a preferred embodiment of the present invention.

2 is a structural view of another amplifying mechanism of the present invention.

1. . . Lens cover opening and closing device

10. . . Drive unit

11. . . Thermal deformation

12. . . Amplifying mechanism

121. . . First lever

121a. . . Pivot

122. . . Second lever

122a. . . Pivot

13. . . Transmission mechanism

131. . . Flexible wire body

132. . . Wheel

20. . . Recovery device

100. . . Projector

110. . . Heat source

120. . . Lens

130. . . lens cap

P1. . . First position

P2. . . Second position

Claims (7)

A lens cover opening and closing device for a projector, the projector having a heat source, a lens and a lens cover, wherein the heat source is used to generate an image beam and heat when the projector is activated; Projecting the aforementioned image beam onto an imaging surface; the lens cover is reciprocable between a first position shielding the lens and a second position away from the lens; the lens cover opening and closing device comprises: a driving The device is connected to the lens cover and has a thermal deformation member located at a position capable of receiving thermal energy generated by the heat generating light source for deforming after receiving the heat energy generated by the heat generating light source And causing the driving device to move the lens cover from the first position to the second position. The lens cover opening and closing device of the projector according to claim 1, wherein the heat deformation member is a wire body made of a material of a shape memory alloy (SMA). The lens cover opening and closing device of the projector of claim 1, wherein the driving device further comprises an amplifying mechanism and a transmission mechanism, the amplifying mechanism is connected to the thermal deformation member, and has an active end connected to the transmission mechanism; The amplifying mechanism is configured to move the working end according to the deformation of the heat deforming member, and the moving end of the working end is larger than the deformation amount of the heat deforming member; the transmission mechanism is connected to the lens cover and driven by the working end The lens cover is moved from the first position to the second position. The lens cover opening and closing device of the projector of claim 3, wherein the amplifying mechanism comprises a first lever and a second lever, one end of the first lever is connected to the thermal deformation member, and the other end is connected to the second lever One end is connected, and the fulcrum of the first lever is located on the first lever and is close to one end of the thermal deformation member; the other end of the second lever is connected to the transmission mechanism, and the fulcrum of the second lever is located at the second The lever is close to one end of the first lever. The lens cover opening and closing device of the projector of claim 4, wherein the transmission mechanism comprises a flexible wire body, one end of which is connected to the second lever, and the other end is connected to the lens cover. The lens cover opening and closing device of the projector of claim 3, wherein the amplifying mechanism comprises a fixed rotating shaft, a wheel body disposed on the rotating shaft and a flexible wire body; the wheel body having the rotating shaft a first circumferential surface and a second circumferential surface of the center, wherein a circumference of the second circumferential surface is greater than a circumference of the first circumferential surface; one end of the flexible wire body is connected to the heat deformation member, and the other end Connected to the first wheel surface; the transmission mechanism includes a flexible wire body, one end of which is connected to the second wheel surface, and the other end is connected to the lens cover. The lens cover opening and closing device of the projector of claim 1, further comprising a returning device coupled to the lens cover for providing a force when the projector is closed, thereby driving the lens cover from the second position Move to the first position.