Foldable projection support
By using the combination of angle positioning part and elastic parts in the projection bracket, the problems of unstable angle adjustment and inability to reduce the volume in the prior art are solved, and the effects of convenient angle adjustment and volume reduction are achieved.
Patent Information
- Application Number
- CN202420560900.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-21
- Publication Date
- 2025-01-07
- Estimated Expiration
- 2034-03-21
AI Technical Summary
The existing projection brackets are unstable and inconvenient to operate when adjusting the angle, and are difficult to reduce the packaging volume, affecting transportation and storage.
A foldable projection bracket is designed, and a first elastic member is combined with a plurality of angle positioning parts and clutch parts. The clutch is driven away from the angle positioning part by unlocking parts, and the relative angle between the support frame and the base is achieved by locating the elastic member. The angle is adjusted stably, which facilitates angle adjustment and reduces the volume by rotating storage.
The stable angle adjustment between the support frame and the base is achieved, which is easy to use, and reduces the volume during storage and reduces transportation costs.
Smart Images
Figure CN222316495U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a foldable projection bracket. Background Art
[0002] At present, in order to install a projection device on a desktop, a projection bracket is usually required. The projection bracket generally includes a bracket body and a pan / tilt head provided on the bracket body for connecting the projection device. Among them, the general bracket body is large in size and cannot be stored into a smaller size, which is not conducive to packaging and transportation.
[0003] To this end, in the related technology, the bracket body is configured to include a base and a support member that can be rotatably stored on the base. The pan / tilt head is arranged on the support member, and the support member is tightened to the base by horizontal bolts. This can not only enable the support member to be rotatably stored in the base to reduce the volume of packaging and transportation, but also enable the angle of the support member relative to the base to be adjusted.
[0004] However, the method of tightening the horizontal bolts relies on friction to prevent the support from rotating relative to the base. The projection equipment on the gimbal is heavy, and it is difficult to keep the angle between the support and the base relatively fixed when the bolts are tightened. After long-term use, the projection equipment on the bracket body will sway to varying degrees, and it is also very inconvenient to adjust the angle position. Utility Model Content
[0005] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model provides a foldable projection stand which is stable after angle adjustment and convenient for angle adjustment.
[0006] A foldable projection bracket according to an embodiment of the utility model includes: a base, wherein the lower side of the base has a placement plane; a support frame, which is rotatably connected to the base via a transverse rotating shaft and can be rotated around the rotating shaft to be folded on the side of the base or unfolded relative to the base; a pan / tilt head, which is arranged on the support frame and is used to install a projection device; a plurality of angle positioning parts, which are arranged on one of the base and the support frame, and the plurality of angle positioning parts are distributed around the axial circumference of the rotating shaft; a clutch, which is arranged on the other of the base and the support frame and can move along the axial direction of the rotating shaft, and the clutch is connected to a first elastic part that drives the clutch to be combined with one of the angle positioning parts; an unlocking part, which is connected to the clutch and can drive the clutch to move and separate from the angle positioning part.
[0007] A foldable projection stand according to an embodiment of the utility model has at least the following beneficial effects:
[0008] When adjusting the unfolding angle of the support frame relative to the base, the above-mentioned foldable projection bracket first uses the unlocking member to drive the clutch member to separate from the angle positioning part, and then the support frame is rotated to align the clutch member with one of the angle positioning parts. The clutch member is combined with the angle positioning part under the action of the first elastic member, thereby positioning the relative angular position of the support frame and the base, achieving the effect of stability after angle adjustment and convenient angle adjustment, and the support frame can also be rotated and folded on the side of the base to reduce the volume of packaging and transportation.
[0009] In some embodiments of the utility model, the angle positioning portion is a positioning through-hole distributed on the base around the axial circumference of the rotating shaft, the clutch member is a latch arranged for axial sliding parallel to the rotating shaft, the two ends of the first elastic member respectively abut against the support frame and the end of the latch to drive the latch to be inserted into the positioning through-hole, and the unlocking member includes a plurality of ejector pins corresponding to each of the positioning through-holes, and the ejector pins can be extended into the corresponding positioning through-holes to eject the latch.
[0010] In some embodiments of the utility model, two latches are provided, and the two latches are symmetrical about the axial center of the rotating shaft. The even number of positioning through holes is divided into at least two positioning hole groups, and the positioning hole group consists of two positioning through holes that are symmetrical about the axial center of the rotating shaft.
[0011] In some embodiments of the utility model, the base is a U-shaped bracket, the support frame is rotatably connected between the two ends of the U-shaped bracket, the two rotating shafts are respectively passed through the two ends of the U-shaped bracket and the corresponding side walls of the support frame, and the support frame can be rotatably stored in the internal area of the U-shaped bracket.
[0012] In some embodiments of the present invention, a first recessed groove is provided in the side wall of the support frame facing the end of the U-shaped bracket, a first guide block is installed in the first recessed groove, the first guide block is provided with a first guide hole for the pin to movably pass through, the two ends of the first elastic member respectively abut against the bottom wall of the first recessed groove and one end of the pin to drive the other end of the pin to be inserted into the positioning through hole along the first guide hole and push the ejector pin, and the unlocking member also includes a pressing block that contacts the ejector pin to push the ejector pin to eject the pin out of the positioning through hole.
[0013] In some embodiments of the utility model, a shaft sleeve portion for the rotating shaft to pass through is provided in the middle portion of the first guide block, a circular ring positioning groove is provided on the outer periphery of the shaft sleeve portion of the first guide block, the first guide hole passes through the circular ring positioning groove, the first elastic member is a spring member sleeved on the outside of the rotating shaft, and one end of the spring member away from the first recessed groove is inserted into the circular ring positioning groove and pushes the end of the pin.
[0014] In some embodiments of the present invention, the end of the U-shaped bracket is provided with a second groove facing the support frame, a second pancake-shaped guide block is installed in the second groove, the positioning hole is arranged to penetrate the second guide block along an axial direction parallel to the rotating shaft, the outer wall of the end of the U-shaped bracket is provided with a third groove for accommodating the pressing block, the U-shaped bracket is provided with a second guide hole penetrating the second groove and the third groove and connected with the positioning hole, the ejector pin is penetrated through the second guide hole and contacts with the pressing block.
[0015] In some embodiments of the utility model, a threaded column is provided at one end of the rotating shaft, and a threaded rod is provided at the other end of the rotating shaft. A limiting head close to the threaded column is provided on the rotating shaft. The threaded rod passes through the U-shaped bracket, the second guide block and the first guide block in sequence to thread the support frame, and the limiting head abuts against the bottom wall of the third sink groove. The pressing block is provided with an internal threaded hole matching the threaded column and an active cavity connected to the internal threaded hole. The active cavity is extended along the length direction of the rotating shaft. The threaded column passes through the internal threaded hole to enter the active cavity and can move telescopically relative to the active cavity.
[0016] In some embodiments of the present invention, the outer circumferential wall of the pressing block matches the shape of the inner circumferential wall of the third groove, and a second elastic member is provided between the end face of the threaded column and the bottom of the movable cavity to drive the pressing block to slide in a direction away from the pin.
[0017] In some embodiments of the utility model, the inner circumferential wall of the first trough is provided with a first strip rib extending along its depth direction, the first guide block is provided with a first strip groove tightly matched with the first strip rib, the inner circumferential wall of the second trough is provided with a second strip rib extending along its depth direction, and the second guide block is provided with a second strip groove tightly matched with the second strip rib.
[0018] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:
[0020] Figure 1 This is a structural schematic diagram of an embodiment of the foldable projection stand of the utility model in a storage state;
[0021] Figure 2 for Figure 1 A schematic diagram of the structure of an embodiment at a certain unfolding angle;
[0022] Figure 3 for Figure 2 A schematic cross-sectional view of the rotational connection between the base and the support frame of an embodiment;
[0023] Figure 4 for Figure 2 A schematic diagram of a partial structural decomposition of an embodiment;
[0024] Figure 5 for Figure 4 Schematic diagram from another perspective. DETAILED DESCRIPTION
[0025] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.
[0026] In the description of the present invention, it should be understood that descriptions involving orientation, such as the orientations or positional relationships indicated by terms such as "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside", etc., are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.
[0027] In the description of the present utility model, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood to exclude the number itself, and "above", "below", "within" etc. are understood to include the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.
[0028] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0029] See also Figures 1 to 3 A foldable projection bracket according to an embodiment of the utility model comprises: a base 100, wherein the lower side of the base 100 has a placement plane; a support frame 200, which is rotatably connected to the base 100 via a horizontal rotating shaft 300 and can be rotated around the rotating shaft 300 to be folded on the side of the base 100 or unfolded relative to the base 100; a pan head 400, which is arranged on the support frame 200 and is used to install a projection device; a plurality of angle positioning parts, which are arranged on one of the base 100 and the support frame 200, and the plurality of angle positioning parts are distributed around the axial circumference of the rotating shaft 300; a clutch, which is arranged on the other of the base 100 and the support frame 200 and can move along the axial direction of the rotating shaft 300, and the clutch is connected to a first elastic member 700 that drives the clutch to be combined with one of its angle positioning parts; an unlocking member 800, which is connected to the clutch and can drive the clutch to move and separate from the angle positioning part.
[0030] When adjusting the unfolding angle of the support frame 200 relative to the base 100, the above-mentioned foldable projection stand first uses the unlocking member 800 to drive the clutch member to separate from the angle positioning portion, and then rotates the support frame 200 to align the clutch member with one of the angle positioning portions. The clutch member is combined with the angle positioning portion under the action of the first elastic member 700, thereby positioning the relative angle position of the support frame 200 and the base 100, achieving the effect of stability after angle adjustment and convenient angle adjustment, and the support frame 200 can also be rotated and folded on the side of the base 100 to reduce the volume of packaging and transportation.
[0031] See also Figures 3 to 5In some embodiments of the utility model, the angle positioning portion is a positioning through hole 910 distributed on the base 100 around the axial circumference of the rotating shaft 300, the clutch member is a latch 600 slidably arranged parallel to the axial direction of the rotating shaft 300, and the two ends of the first elastic member 700 respectively abut against the end of the support frame 200 and the latch 600 to drive the latch 600 to insert into the positioning through hole 910, and the unlocking member 800 includes a plurality of ejector pins 810 corresponding to each positioning through hole 910, and the ejector pin 810 can extend into the corresponding positioning through hole 910 to eject the latch 600. It can be understood that when the user applies pressure on the ejector pin 810, the ejector pin 810 pushes out the pin 600 in the positioning hole 910. At this time, the support frame 200 and the base 100 can rotate relative to each other. When the support frame 200 rotates relative to the base 100 until the pin 600 is aligned with another positioning hole 910, pressure is no longer applied to the ejector pin 810. The pin 600 is reinserted into the positioning hole 910 under the action of the first elastic member 700. The insertion of the pin 600 into the positioning hole 910 can prevent the support frame 200 and the base 100 from rotating relative to each other, thereby ensuring that the projection equipment on the gimbal 400 can be stable.
[0032] See also Figure 3 , Figure 4 and Figure 5 In some embodiments of the utility model, two latches 600 are provided, and the two latches 600 are symmetrical about the axial center of the rotating shaft 300. The even number of positioning holes 910 is divided into at least two positioning hole groups, and the positioning hole group is composed of two positioning holes 910 symmetrical about the axial center of the rotating shaft 300. It can be understood that the two ejector pins 810 can simultaneously face the two positioning holes 910 of a positioning hole group, so as to avoid the single ejector pin 810 from being easily deformed by force, and improve the stability of the foldable projection bracket after the angle adjustment. In this embodiment, there are two positioning hole groups. When the two latches 600 enter one of the positioning hole groups, the support frame 200 is lifted by an angle of 30° relative to the base 100. When the two latches 600 enter the other positioning hole group, the support frame 200 is lifted by an angle of 90° relative to the base 100. It should be noted that the base 100 can be placed on a desktop for use, or it can be fixed on a wall by other structures for use.
[0033] See also Figure 1 and Figure 2 In some embodiments of the present invention, the base 100 is a U-shaped bracket, the support frame 200 is rotatably connected between the two ends of the U-shaped bracket, and the two rotating shafts 300 are respectively passed through the two ends of the U-shaped bracket and the corresponding side walls of the support frame 200. The support frame 200 can be rotatably stored in the internal area of the U-shaped bracket, thereby further reducing the volume of the foldable projection bracket when stored, and reducing the cost required for packaging, transportation or storage.
[0034] See also Figure 4 and Figure 5 In some embodiments of the utility model, a first recessed groove 210 is provided in the side wall of the support frame 200 facing the end of the U-shaped bracket, a first guide block 500 is installed in the first recessed groove 210, and the first guide block 500 is provided with a first guide hole 510 for the latch 600 to movably pass through. The two ends of the first elastic member 700 respectively abut against the bottom wall of the first recessed groove 210 and one end of the latch 600 to drive the other end of the latch 600 to be inserted into the positioning through hole 910 along the first guide hole 510 and push the ejector pin 810. The unlocking member 800 also includes a pressing block 820 that contacts the ejector pin 810 to be able to push the ejector pin 810 to push the latch 600 out of the positioning through hole 910. It is understandable that the first sink 210 is provided to provide space for the installation of the first elastic member 700, and the first guide hole 510 on the first guide block 500 is used to guide the latch 600 to reciprocate along the axial direction of the rotating shaft 300. When the latch 600 is pushed by the first elastic member 700 and inserted into the positioning through hole 910, the ejector pin 810 is also pressed to exit the positioning through hole 910. At this time, the first guide block 500 is connected to the U-shaped bracket through the latch 600, and the support frame 200 cannot rotate relative to the U-shaped bracket. The above structure is simple in construction, the assembly steps are simple, and the product processing difficulty and precision are relatively low.
[0035] See also Figure 4 In some embodiments of the present invention, a sleeve portion 520 is provided in the middle of the first guide block 500 for the shaft 300 to pass through, and a circular positioning groove 530 is provided on the outer periphery of the sleeve portion 520 of the first guide block 500, see Figures 3 to 5 , the first guide hole 510 passes through the circular positioning groove 530, the first elastic member 700 is a spring member sleeved on the outside of the rotating shaft 300, and the end of the spring member away from the first sink groove 210 is inserted into the circular positioning groove 530 and pushes the end of the plug 600. It can be understood that the rotation shaft 300 passing through the spring member helps to limit the radial movement of the spring member, and the circular positioning groove 530 locates a circle of spiral units at the end of the spring member, ensuring that the spring member can abut against one end of the plug 600 to push the other end of the plug 600 into the corresponding positioning through hole 910.
[0036] See also Figure 3 , Figure 4 and Figure 5In some embodiments of the utility model, a second groove 110 facing the support frame 200 is provided at the end of the U-shaped bracket, a second pancake-shaped guide block 900 is installed in the second groove 110, and a positioning through hole 910 is arranged to penetrate the second guide block 900 along an axial direction parallel to the rotating shaft 300. The outer side wall of the end of the U-shaped bracket is provided with a third groove 120 for accommodating a pressing block 820. The pressing block 820 can reciprocate along the depth direction of the third groove 120. The U-shaped bracket is provided with a second guide hole 130 that penetrates the second groove 110 and the third groove 120 and is connected to the positioning through hole 910. The ejector pin 810 is penetrated through the second guide hole 130 and contacts the pressing block 820. When the latch 600 is inserted into one of the positioning holes 910, the support frame 200 is stabilized at a certain angle relative to the base 100. When the user applies force to the pressing block 820 in the direction of compressing the first elastic member 700, the pressing block 820 drives each ejector pin 810 to extend into each positioning hole 910, and the latch 600 exits the second guide block 900. At this time, the second guide block 900 can rotate freely relative to the first guide block 500, that is, the base 100 can rotate freely relative to the support frame 200. In order to quickly unfold the support frame 200 from the base 100, when the support frame 200 is rotated and stored in the inner area of the U-shaped bracket, the end of the latch 600 away from the first elastic member 700 abuts against the side wall of the second guide block 900 facing the first guide block 500, and the support frame 200 can be directly unfolded from the base 100 without using the unlocking member 800.
[0037] See also Figure 3In some embodiments of the utility model, a threaded column 310 is provided at one end of the rotating shaft 300, a threaded rod 320 is provided at the other end of the rotating shaft 300, a stopper head 330 is provided on the rotating shaft 300 near the threaded column 310, the threaded rod 320 passes through the U-shaped bracket, the second guide block 900 and the first guide block 500 in sequence to thread the support frame 200, and the stopper head 330 abuts against the bottom wall of the third sink 120, so that the support frame 200 can rotate relative to the U-shaped bracket, and prevent the support frame 200 and the U-shaped bracket from moving relative to each other in the length direction of the rotating shaft 300. The pressing block 820 is provided with an internal threaded hole 821 matching the threaded column 310 and an active cavity 822 connected to the internal threaded hole 821, the active cavity 822 is extended along the length direction of the rotating shaft 300, and the threaded column 310 passes through the internal threaded hole 821 to enter the active cavity 822 and can telescopically move relative to the active cavity 822. It should be noted that after the threaded column 310 of the rotating shaft 300 is screwed through the internal threaded hole 821 of the pressing block 820, the threaded column 310 enters the movable cavity 822. At this time, the pressing block 820 will not be separated from the rotating shaft 300 due to the push of the ejector pin 810. The movable cavity 822 provides a travel space for the pressing block 820 to move relative to the threaded column 310, playing the dual role of limiting and preventing disengagement, and the structure is very ingenious.
[0038] See also Figure 3 In some embodiments of the present invention, the outer peripheral wall of the pressing block 820 matches the shape of the inner peripheral wall of the third sink groove 120, and a second elastic member 830 is provided between the end surface of the threaded column 310 and the bottom of the movable cavity 822 to drive the pressing block 820 to slide in a direction away from the latch 600. Since the outer peripheral wall of the pressing block 820 matches the shape of the inner peripheral wall of the third sink groove 120, the third sink groove 120 acts as a sliding guide for the pressing block 820. When the user no longer applies force to the pressing block 820, the pressing block 820 can be smoothly reset under the action of the second elastic member 830, so that the ejector pin 810 can be smoothly ejected from the positioning through hole 910 by the latch 600.
[0039] See also Figure 4 and Figure 5In some embodiments of the utility model, the inner circumferential wall of the first sink 210 is provided with a first strip rib 220 extending along the depth direction thereof, the first guide block 500 is provided with a first strip groove 540 tightly matched with the first strip rib 220, the inner circumferential wall of the second sink 110 is provided with a second strip rib 111 extending along the depth direction thereof, and the second guide block 900 is provided with a second strip groove 920 tightly matched with the second strip rib 111. It should be noted that after the shaft 300 is installed, the first guide block 500 is fixed relative to the support frame 200, and the second guide block 900 is fixed relative to the base 100. However, during the installation of the shaft 300, if the first guide block 500 and the second guide block 900 are not pre-fixed, it will cause displacement during assembly, resulting in assembly difficulties. The above structure pre-fixes the first guide block 500 and the second guide block 900 in a tight-fitting manner, which is very convenient when assembling the product.
[0040] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0041] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.
Claims
1. A foldable projection stand, characterized in that: include: A base (100), wherein the lower side of the base (100) has a placement plane; The support frame (200) is rotatably connected to the base (100) via a horizontally placed rotating shaft (300), and can be rotated around the rotating shaft (300) to be folded on the side of the base (100) or unfolded relative to the base (100); A pan / tilt platform (400), arranged on the support frame (200) and used for installing a projection device; A plurality of angle positioning portions, provided on one of the base (100) and the support frame (200), the plurality of angle positioning portions being distributed around the axial circumference of the rotating shaft (300); A clutch member, provided on the other of the base (100) and the support frame (200), movable along the axial direction of the rotating shaft (300), the clutch member being connected to a first elastic member (700) for driving the clutch member to engage with one of the angle positioning portions; An unlocking member (800) is connected to the clutch member and can drive the clutch member to move and separate from the angle positioning portion.
2. The foldable projection stand according to claim 1, characterized in that: The angle positioning portion is a positioning through hole (910) distributed on the base (100) around the axial circumference of the rotating shaft (300); the clutch member is a latch (600) slidably arranged parallel to the axial direction of the rotating shaft (300); the two ends of the first elastic member (700) respectively abut against the support frame (200) and the end of the latch (600) to drive the latch (600) to be inserted into the positioning through hole (910); the unlocking member (800) includes a plurality of ejector pins (810) corresponding to each of the positioning through holes (910); the ejector pins (810) can extend into the corresponding positioning through holes (910) to eject the latch (600).
3. The foldable projection stand according to claim 2, characterized in that: Two latches (600) are provided, and the two latches (600) are symmetrical about the axial center of the rotating shaft (300). The even number of positioning through holes (910) are divided into at least two positioning hole groups, and the positioning hole group consists of two positioning through holes (910) that are symmetrical about the axial center of the rotating shaft (300).
4. The foldable projection stand according to claim 2, characterized in that: The base (100) is a U-shaped bracket, the support frame (200) is rotatably connected between the two ends of the U-shaped bracket, the two rotating shafts (300) are respectively penetrated through the two ends of the U-shaped bracket and the corresponding side walls of the support frame (200), and the support frame (200) can be rotatably stored in the internal area of the U-shaped bracket.
5. The foldable projection stand according to claim 4, characterized in that: The side wall of the support frame (200) facing the end of the U-shaped bracket is concavely provided with a first groove (210), and a first guide block (500) is installed in the first groove (210). The first guide block (500) is provided with a first guide hole (510) for the latch (600) to movably pass through. The two ends of the first elastic member (700) respectively abut against the bottom wall of the first groove (210) and one end of the latch (600) to drive the other end of the latch (600) to be inserted into the positioning through hole (910) along the first guide hole (510) and push the ejector pin (810). The unlocking member (800) also includes a pressing block (820) that contacts the ejector pin (810) so as to push the ejector pin (810) to eject the latch (600) out of the positioning through hole (910).
6. The foldable projection stand according to claim 5, characterized in that: A shaft sleeve portion (520) is provided in the middle of the first guide block (500) for the shaft (300) to pass through, and a circular ring positioning groove (530) is provided on the outer periphery of the shaft sleeve portion (520) of the first guide block (500), and the first guide hole (510) passes through the circular ring positioning groove (530). The first elastic member (700) is a spring member sleeved on the outside of the shaft (300), and one end of the spring member away from the first recessed groove (210) is inserted into the circular ring positioning groove (530) and pushes against the end of the latch (600).
7. The foldable projection stand according to claim 5, characterized in that: The end of the U-shaped bracket is provided with a second groove (110) facing the support frame (200), and a second pancake-shaped guide block (900) is installed in the second groove (110). The positioning hole (910) is arranged to penetrate the second guide block (900) along an axial direction parallel to the rotating shaft (300). The outer wall of the end of the U-shaped bracket is provided with a third groove (120) for accommodating the pressing block (820). The U-shaped bracket is provided with a second guide hole (130) that penetrates the second groove (110) and the third groove (120) and is connected to the positioning hole (910). The ejector pin (810) is penetrated in the second guide hole (130) and contacts with the pressing block (820).
8. The foldable projection stand according to claim 7, characterized in that: A threaded column (310) is provided at one end of the rotating shaft (300), a threaded rod (320) is provided at the other end of the rotating shaft (300), a limiting head (330) close to the threaded column (310) is provided on the rotating shaft (300), the threaded rod (320) passes through the U-shaped bracket, the second guide block (900) and the first guide block (500) in sequence to threadably fix the support frame (200), and the limiting head (330) abuts against the first guide block (500). The bottom wall of the three sink grooves (120), the pressing block (820) is provided with an internal threaded hole (821) matching the threaded column (310) and an active cavity (822) connected to the internal threaded hole (821), the active cavity (822) is extended along the length direction of the rotating shaft (300), the threaded column (310) passes through the internal threaded hole (821) to enter the active cavity (822) and can be telescopically moved relative to the active cavity (822).
9. The foldable projection stand according to claim 8, characterized in that: The outer wall of the pressing block (820) matches the shape of the inner wall of the third sink groove (120), and a second elastic member (830) is provided between the end face of the threaded column (310) and the bottom of the movable cavity (822) to drive the pressing block (820) to slide in a direction away from the latch (600).
10. The foldable projection stand according to claim 7, characterized in that: The inner circumferential wall of the first trough (210) is provided with a first strip rib (220) extending along its depth direction, the first guide block (500) is provided with a first strip groove (540) tightly matched with the first strip rib (220), the inner circumferential wall of the second trough (110) is provided with a second strip rib (111) extending along its depth direction, and the second guide block (900) is provided with a second strip groove (920) tightly matched with the second strip rib (111).