U.S. patent application number 10/994628 was filed with the patent office on 2006-05-25 for reflective mechanism for stage lamp.
Invention is credited to Ming-Cheng Chang.
Application Number | 20060109574 10/994628 |
Document ID | / |
Family ID | 36460696 |
Filed Date | 2006-05-25 |
United States Patent
Application |
20060109574 |
Kind Code |
A1 |
Chang; Ming-Cheng |
May 25, 2006 |
REFLECTIVE MECHANISM FOR STAGE LAMP
Abstract
A reflective mechanism includes a base fixed on a support member
of a stage lamp, a bracket fixed on the base, a mirror frame, and a
reflective mirror mounted on the mirror frame. A hollow shaft
rotatably extends through an axial hole of the base and includes a
fork on an end thereof. The hollow shaft is driven by a first motor
mounted on the base to turn about a longitudinal axis of the hollow
shaft. The mirror frame includes a pivotal portion pivotally
mounted to the fork of the hollow shaft. The pivotal portion of the
mirror frame is driven by a second motor to pivot through
transmission by an endless cord that extends through the hollow
shaft without interfering with rotation of the hollow shaft.
Inventors: |
Chang; Ming-Cheng;
(Yungkang, TW) |
Correspondence
Address: |
NIKOLAI & MERSEREAU, P.A.
900 SECOND AVENUE SOUTH
SUITE 820
MINNEAPOLIS
MN
55402
US
|
Family ID: |
36460696 |
Appl. No.: |
10/994628 |
Filed: |
November 22, 2004 |
Current U.S.
Class: |
359/877 ;
359/872 |
Current CPC
Class: |
F21V 17/02 20130101;
F21S 10/06 20130101; F21W 2131/406 20130101; F21V 7/0008 20130101;
F21V 14/04 20130101 |
Class at
Publication: |
359/877 ;
359/872 |
International
Class: |
G02B 5/08 20060101
G02B005/08 |
Claims
1. A reflective mechanism for a stage lamp, the stage lamp
including a body and a support member mounted on the body, the
reflective mechanism comprising: a base fixed on the support
member, the base including an axial hole; a first motor mounted to
the base, the first motor including an output shaft with a first
gear; a first transmission device including a hollow shaft
rotatably extending through the axial hole of the base and a first
driven gear mounted on the hollow shaft to turn therewith, the
first driven gear being meshed with and driven by the first gear,
the hollow shaft further including a fork on an end thereof; a
bracket including a bottom fixed on the base and a wall extending
from the bottom; a second motor mounted on the wall of the bracket,
the second motor including an output shaft with a second gear; a
second transmission device including an endless cord and a second
driven gear meshed with the second gear, the second driven gear
including a pulley extending from a side thereof; a mirror frame
including a bottom plate and a pivotal portion, the pivotal portion
being pivotally mounted to the fork of the hollow shaft, the
endless cord being wound around the pulley and the pivotal portion
of the mirror frame, allowing joint rotation of the mirror frame
and the second driven gear, the endless cord extending through the
hollow shaft without interfering with rotation of the hollow shaft;
and a reflective mirror mounted on the bottom plate of the mirror
frame to turn therewith; wherein when the first motor turns, the
mirror frame together with reflective mirror rotates about a
longitudinal axis of the hollow shaft; and wherein when the second
motor turns, the mirror frame together with the reflective mirror
pivots about a pivotal axis of the pivotal portion.
2. The reflective mechanism for a stage lamp as claimed in claim 1,
with the longitudinal axis of the hollow shaft being parallel to an
incident light from a light source mounted in the body of the stage
lamp.
3. The reflective mechanism for a stage lamp as claimed in claim 1,
with the pivotal axis of the pivotal portion being orthogonal to
the longitudinal axis of the hollow shaft.
4. The reflective mechanism for a stage lamp as claimed in claim 1,
with the first driven gear of the first transmission device
including a plurality of inner teeth, with the first transmission
device further including a third gear securely mounted on the
hollow shaft to turn therewith, and with the third gear including a
plurality of outer teeth for securely engaging with the inner teeth
of the first driven gear to turn therewith.
5. The reflective mechanism for a stage lamp as claimed in claim 4,
with the third gear including a groove in a side thereof, with the
base including a restraining member received in the groove of the
third gear, limiting joint rotational movement of the third gear
and the hollow shaft, thereby limiting joint rotational movement of
the mirror frame and the reflective mirror.
6. The reflective mechanism for a stage lamp as claimed in claim 1,
with the pivotal portion of the mirror including two spaced stops
for limiting pivotal movement of the mirror frame and the
reflective mirror.
7. The reflective mechanism for a stage lamp as claimed in claim 1,
with the pulley including an annular groove, with the pivotal
portion of the mirror frame including an annular groove, and with
the endless cord being wound around the annular groove of the
pulley and the annular groove of the pivotal portion.
8. The reflective mechanism for a stage lamp as claimed in claim 1,
with the fork of the hollow shaft including two spaced branches,
and with two tensioning rollers rotatably mounted between the
branches for guiding and tensioning the endless cord.
9. The reflective mechanism for a stage lamp as claimed in claim 1,
with the fork of the hollow shaft including two spaced branches
having aligned holes, with the pivotal portion including a hole,
with the reflective mechanism further including a pin extending
through the aligned holes of the fork and the hole of the pivotal
portion.
10. The reflective mechanism for a stage lamp as claimed in claim
8, with the fork of the hollow shaft including two spaced branches
having aligned holes, with the pivotal portion including a hole,
with the reflective mechanism further including a pin extending
through the aligned holes of the fork and the hole of the pivotal
portion.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a reflective mechanism for
a stage lamp. In particular, the present invention relates to a
reflective mechanism for a stage lamp that includes a rotatable
reflective mirror.
[0003] 2. Description of the Related Art
[0004] A stage lamp provides colorful light effects for a stage.
FIG. 1 of the drawings illustrates a conventional stage lamp and
FIG. 2 is an exploded perspective view of a reflective mechanism of
the conventional stage lamp. The stage lamp includes a body 1, a
light source 11 mounted in the body 1, a lens 12 mounted in the
body 1, and a reflective mechanism 2. The reflective mechanism 2
includes a fixed frame 24 mounted on the body 1, a rotary frame 25,
a first motor 21 mounted on the fixed frame 24 for rotating the
rotary frame 25, a mirror frame 26, a reflective mirror 23 mounted
on the mirror frame 26, and a second motor 22 mounted on the rotary
frame 25 for rotating the mirror frame 26.
[0005] When the first motor 21 turns, the rotary frame 25 rotates
such that the reflective mirror 23 rotates about an axis parallel
to an incident light from the light source 11. When the second
motor 22 turns, the reflective mirror 23 rotates about an axis
transverse to the axis. Thus, various light effects can be
obtained. However, the first motor 21 must have a large horsepower
for driving the rotary frame 25 carrying the second motor 22 and
the mirror frame 26. Further, the rotary frame 25 and the mirror
frame 26 are continuously changing their speed and direction such
that both of the first motor 21 and the second motor 22 must have a
large horsepower to overcome the rotational inertia. Further,
positioning of the second motor 22 on the rotary frame 25 is not
easy, as the rotary frame 25 rotates frequently when in use.
SUMMARY OF THE INVENTION
[0006] In accordance with a first aspect of the present invention,
a reflective mechanism is provided for a stage lamp including a
body and a support member mounted on the body. The reflective
mechanism comprises a base fixed on the support member, a first
motor mounted to the base and including an output shaft with a
first gear, a first transmission device, a bracket including a
bottom fixed on the base and a wall extending from the bottom, a
second motor mounted on the wall of the bracket and including an
output shaft with a second gear, a second transmission device, a
mirror frame, and a reflective mirror mounted on a bottom plate of
the mirror frame to turn therewith.
[0007] The first transmission device includes a hollow shaft
rotatably extending through an axial hole of the base and a first
driven gear mounted on the hollow shaft to turn therewith. The
first driven gear is meshed with and driven by the first gear. The
hollow shaft further includes a fork on an end thereof. The second
transmission device includes an endless cord and a second driven
gear meshed with the second gear. The second driven gear includes a
pulley extending from a side thereof.
[0008] The mirror frame includes a pivotal portion pivotally
mounted to the fork of the hollow shaft. The endless cord is wound
around the pulley and the pivotal portion of the mirror frame,
allowing joint rotation of the mirror frame and the second driven
gear. The endless cord extends through the hollow shaft without
interfering with rotation of the hollow shaft.
[0009] When the first motor turns, the mirror frame together with
reflective mirror rotates about a longitudinal axis of the hollow
shaft. When the second motor turns, the mirror frame together with
the reflective mirror pivots about a pivotal axis of the pivotal
portion.
[0010] Preferably, the longitudinal axis of the hollow shaft is
parallel to an incident light from a light source mounted in the
body of the stage lamp, and the pivotal axis of the pivotal portion
is orthogonal to the longitudinal axis of the hollow shaft.
[0011] In an embodiment of the invention, the first driven gear of
the first transmission device includes a plurality of inner teeth.
The first transmission device further includes a third gear
securely mounted on the hollow shaft to turn therewith. The third
gear includes a plurality of outer teeth for securely engaging with
the inner teeth of the first driven gear to turn therewith.
[0012] The third gear includes a groove in a side thereof. The base
includes a restraining member received in the groove of the third
gear, limiting joint rotational movement of the third gear and the
hollow shaft, thereby limiting joint rotational movement of the
mirror frame and the reflective mirror.
[0013] The pivotal portion of the mirror includes two spaced stops
for limiting pivotal movement of the mirror frame and the
reflective mirror.
[0014] Each of the pulley and the pivotal portion of the mirror
frame includes an annular groove. The endless cord is wound around
the annular groove of the pulley and the annular groove of the
pivotal portion.
[0015] The fork of the hollow shaft includes two spaced branches,
and two tensioning rollers are rotatably mounted between the
branches for guiding and tensioning the endless cord.
[0016] The branches of the fork of the hollow shaft include aligned
holes, and the pivotal portion includes a hole. A pin extends
through the aligned holes of the fork and the hole of the pivotal
portion.
[0017] By such an arrangement, the reflective mirror in accordance
with the present invention can be driven with low-horsepower
motors, as the rotational inertia to be overcome is much smaller as
compared to the conventional design.
[0018] Other objectives, advantages, and novel features of the
invention will become more apparent from the following detailed
description when taken in conjunction with the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a partly sectioned side view of a conventional
stage lamp.
[0020] FIG. 2 is an exploded perspective view of a reflective
mechanism of the conventional stage lamp.
[0021] FIG. 3 is a side view of a stage lamp with a reflective
mechanism in accordance with the present invention.
[0022] FIG. 4 is a sectional view of the reflective mechanism in
accordance with the present invention.
[0023] FIG. 5 is a perspective view of the reflective mechanism in
accordance with the present invention, wherein a casing is removed
to show an interior structure thereof.
[0024] FIG. 6 is an exploded perspective view of the reflective
mechanism in accordance with the present invention.
[0025] FIG. 7 is a side view of the reflective mechanism in FIG. 4,
wherein a casing of the reflective mechanism is removed to show
interior structure.
[0026] FIG. 8 is a sectional view similar to FIG. 4, illustrating
rotation of a reflective mirror in a direction.
[0027] FIG. 9 is a sectional view similar to FIG. 4, illustrating
rotation of the reflective mirror in an orthogonal direction.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0028] Referring to FIGS. 3 through 6, a stage lamp in accordance
with the present invention comprises a body 3, a support member 4
including an end fixedly mounted to the body 3, and a reflective
mechanism 5 mounted to the other end of the support member 4. A
light source 31 and a rotary disc 32 carrying at least one pattern
are mounted in the body 3. A light beam from the light source 31
passing through a lens (not labeled) and the rotary disc 32 is
incident on the reflective mirror 56 of the reflective mechanism 5
and reflected therefrom. The internal structure of the body 3 is
conventional and therefore not further described.
[0029] The reflective mechanism 5 comprises a base 51 fixed on the
support member 4, a bracket 57 fixed on the base 51, a first motor
52 mounted on the base 51, a second motor 58 mounted on the bracket
57, a first transmission device 53 connected to and driven by the
first motor 52, a second transmission device 54 connected to and
driven by the second motor 58, a mirror frame 55, and the
above-mentioned reflective mirror 56 mounted on the mirror frame
55.
[0030] As illustrated in FIG. 6, the base 51 includes an axial hole
511 in a central portion thereof and a mounting hole 512. A casing
59 is attached to the base 51 for housing most of the elements. The
first motor 52 includes an output shaft 520 extending through the
mounting hole 512, and a gear 512 is securely mounted on the output
shaft 520 of the first motor 52 to turn therewith.
[0031] The first transmission device 53 comprises a hollow shaft
531 rotatably extending through the axial hole 511, a gear 532
securely mounted on the hollow shaft 531 to turn therewith, and a
driven gear 533. In this illustrated embodiment, the driven gear
533 includes a plurality of inner teeth 536 for securely engaging
with outer teeth (not labeled) of the gear 532 to turn therewith.
Further, the driven gear 533 meshes with and thus driven by the
gear 521 of the first motor 52. Thus, when the first motor 52
turns, the hollow shaft 531 rotates about a longitudinal axis
thereof. Preferably, the longitudinal axis of the hollow shaft 531
is parallel to the incident light from the light source 31.
Bearings 534 are mounted between the hollow shaft 531 and a
peripheral wall delimiting the axial hole 511 to allow smooth
rotation.
[0032] The gear 532 includes a groove 537 in a side thereof.
Referring to FIG. 7, a restraining member 513 is mounted on the
base 51 and received in the groove 537 to restrain rotational
movement of the gear 532. Namely, further joint rotation of the
gear 532 and the hollow shaft 531 is not allowed when one of two
end walls delimiting the groove 537 comes in contact with the
restraining member 513. Further, the restraining member 513 forms a
starting point for the hollow shaft 531.
[0033] The bracket 57 includes a bottom 571 fixed on the base 51
and a wall 572 extending upright from the bottom 571. The bottom
571 includes an axial hole 574, and the wall 572 includes a
mounting hole 573. The second motor 58 includes an output shaft 580
rotatably extending through the mounting hole 573. A gear 581 is
mounted on the output shaft 580 to turn therewith.
[0034] The second transmission device 54 includes a driven gear 541
that meshes with and is driven by the gear 581 of the second motor
58. The second transmission device 54 further includes an endless
cord 542. The driven gear 541 is rotatably supported by a plate 543
that is fixed to the wall 572. A pulley 544 extends from a side of
the gear 541 and includes an annular groove (not labeled) around
which a portion 545 of the endless cord 542 is wound. A further
plate 546 is mounted to the pulley 544 to prevent the endless cord
542 from slipping.
[0035] The mirror frame 55 includes a bottom plate 551 on which the
reflective mirror 56 is securely mounted. The mirror frame 55
further includes a pivotal portion 552 extending from the bottom
plate 551 and pivotally connected with an end of the hollow shaft
531. In this illustrated embodiment, the end of the hollow shaft
531 includes a fork 535 having two branches (not labeled) between
which the pivotal portion 552 is mounted, with a pin 530 extending
through a hole 550 of the pivotal portion 552 of the mirror frame
55 and aligned holes 539 of the branches. The pivotal portion 552
of the mirror frame 55 further includes an annular groove 553
around which another portion 547 of the endless cord 542 is wound.
Thus, when the second motor 58 turns, the reflective frame 55 and
the reflective mirror 56 turns about a pivotal axis of the pin 530
through transmission by the driven gear 541 and the endless cord
542. It is noted that the endless cord 542 extends through the
hollow shaft 531 without interfering with rotation of the hollow
shaft 531.
[0036] As illustrated in FIG. 4, two tensioning rollers 538 are
rotatably mounted between the branches of the fork 535 for guiding
and tensioning the endless cord 542. The pivotal portion 554
further includes two spaced stops 554 to limit rotational angle of
the mirror frame 55. Namely, further rotation of the mirror frame
55 is not allowed when any one of the stops 554 comes in contact
with the fork 535. Further, each stops 554 forms a starting point
for the mirror frame 55.
[0037] Referring to FIGS. 4 and 8, when the first motor 52 turns,
the mirror frame 55 together with the reflective mirror 56 turns
about the longitudinal axis of the hollow shaft 531 through
transmission by the driven gear 533, the gear 532, and the hollow
shaft 531 of the first transmission device 53. Referring to FIGS. 4
and 9, when the second motor 58 turns, by transmission of the
driven gear 541 and the endless cord 542 of the second transmission
device 54, the mirror frame 55 together with the reflective mirror
56 pivots about the pivotal axis of the pin 530 that is orthogonal
to the longitudinal axis of the hollow shaft 531. Various light
effects are provided through various reflective angles of the
reflective mirror 56.
[0038] Since the first transmission device 53 and the second
transmission device 54 are independent from each other and since
the rotational inertia of the reflective mirror 56 is small, the
load of each of the first motor 52 and the second motor 58 is
small. Thus, low-horsepower motors can be used. Further, there is
no need to increase the horsepower of the first motor 52, as the
second motor 58 causes no load to the first motor 52. Further,
loosening of the second motor 58 is less likely to occur.
[0039] Although a specific embodiment has been illustrated and
described, numerous modifications and variations are still possible
without departing from the essence of the invention. The scope of
the invention is limited by the accompanying claims.
* * * * *