TWI882610B - Roller curtain pre-tension limit spring stop structure - Google Patents

Abstract

The present invention provides a roller blind pre-tension limit spring stopper structure, which is arranged between a fixing frame and a roller tube at one end of a roller blind, and provides a pre-tension elastic force for stopping the roller tube from rotating when the roller blind stops pushing up or pulling down. The structure comprises a torsion spring assembly, a knob assembly and a stopper housing, wherein the torsion spring assembly comprises a spring joint, a spring bracket, a fixed shaft and a torsion spring, the roller tube is sleeved on the outer side of the torsion spring and connected to the spring bracket, the knob assembly comprises an annular knob, on which a first plug-in slot is arranged, and a fixing block, which is complementarily arranged on the inner side of the knob, on which a second The plug slot is connected to the first plug slot. The driving assembly includes a shaft, a limit block and a compression spring. One end of the shaft is fixed to the spring joint, and the other end is inserted into the second plug slot to connect the knob assembly. The limit block is movably inserted into a socket or hook provided on the shaft and fixed to the socket. The compression spring is between the inner side of the socket and the limit block. The head casing is sleeved on the outer side of the shaft and connected to the winding tube. The inner wall thereof is provided with a plurality of limit grooves. When the limit block is not hooked and fixed to the socket, the limit block is subjected to the tension of the compression spring and abuts against the inner wall or the limit groove of the head casing with the abutment block.

Description

Roller curtain pre-tension limit spring stop structure

This invention is related to the pre-tensioning technology of roller blinds, and more specifically refers to a roller blind pre-tensioning limit spring stopper structure.

According to the knowledge, the structure of the roller curtain that uses the internal torsion spring to control the positioning of the curtain is generally composed of a roller tube, a curtain, a control mechanism and two fixing frames. The roller tube is pivoted between the two fixing frames, and the curtain is connected to the roller tube and can be rolled up or unfolded downward by the rotating roller tube. The control mechanism is set in the roller tube, including a torsion spring and a number of drive components. The torsion spring can keep the position of the curtain after the pull-down or push-up action stops, so as to avoid the unexpected upward retraction or downward unfolding of the curtain. The two fixing frames are used to fix to the indoor installation location such as the ceiling.

The torsion spring of the roller blind needs to have an appropriate pre-tensioning force to enable the roller blind to produce the aforementioned effect of keeping the curtain cloth in position. Most of these pre-tensioning forces are adjusted before leaving the factory, so that consumers can directly install the roller blind and make it work normally. The known pre-tensioning method of the torsion spring is to manually operate the drive assembly to twist the torsion spring an appropriate number of turns and then fix the position of the drive assembly to prevent the torsion spring from reversing and maintain the pre-tensioning force. The number of turns of the torsion spring depends on factors such as the weight of the roller blind assembly, the size of the curtain cloth, and the elastic force of the torsion spring. This is common knowledge in the relevant technical field.

Since it is known that the manual operation of torsion spring pre-tensioning before the roller curtain leaves the factory is not convenient and may cause the pre-tensioning force to be reduced, there are roller curtains that allow consumers to adjust the pre-tensioning force of the torsion spring by themselves after installation, as shown in the Republic of China's new patents No. 635907 and No. 629737. However, if the pre-tensioning force of the torsion spring of the roller curtain is not reduced and the installation of the roller curtain is normal, there is no need for consumers to adjust the pre-tensioning force of the torsion spring by themselves, and the mechanism design of the self-adjusting pre-tensioning force of the torsion spring in these roller curtains is redundant.

The main purpose of the present invention is to provide a roller blind pre-tightening limit spring stopper structure, which not only allows the roller blind to be pre-tightened conveniently before leaving the factory, but also has a very reliable pre-tightening effect. Consumers do not need to perform pre-tightening after installing the roller blind, making the installation of the roller blind very convenient and of great practical value.

Therefore, in order to achieve the above-mentioned purpose, the present invention provides a roller blind pre-tension limit spring stopper structure, which is connected between a fixing frame at one end of a roller blind and a roller tube, and is used to provide a pre-tension elastic force for stopping the roller tube from rotating when the roller blind stops pushing up or pulling down. The structure includes a torsion spring assembly, including a spring joint, a spring bracket, a fixed shaft and a torsion spring. The spring bracket is provided with an axle hole, and the fixing shaft is provided with a torsion spring. One end of the shaft is fixed to the spring joint, and the other end is a shaft hole protruding from the spring bracket. The torsion spring is sleeved on the fixed shaft and between the spring joint and the spring bracket. The coil is sleeved on the outer side of the torsion spring and connected to the spring bracket. A knob assembly includes a knob in a ring shape with a first insertion slot, a fixing block, which is complementary to the inner side of the knob and has a second insertion slot. The second insertion slot is connected to the first plug slot; a driving assembly, including a shaft, a limit block and a compression spring, the shaft including a shaft portion, a plug block and a connecting portion connected between the shaft portion and the plug block, the shaft portion is a fixed spring joint, the plug block is inserted into the second plug slot, so that the shaft is connected to the knob assembly, the connecting portion is recessed with a plug hole, the limit block is inserted into the plug hole, including a contact block and a positioning hook, The positioning hook is elastically offset and protrudes from one end of the limit block, and can be hooked on the inner side of the socket. The compression spring is between the inner side of the socket and the limit block. A control head outer shell is cylindrical, sleeved on the outer side of the shaft and connected to the winding tube, and its inner wall is provided with a plurality of limit grooves. When the positioning hook is not hooked on the inner side of the socket, the limit block is subjected to the tension of the compression spring and abuts against the inner wall or the limit groove of the control head outer shell with the abutment block.

Preferably, the fixing block is fixed to a fixing frame of the roller blind by a plurality of connecting parts after the torsion spring generates a pre-tightening force, and the fixing frame is used to fix the roller blind to an indoor installation position.

Preferably, the two ends of the winding tube are sleeved on the outer side of the spring bracket and the head casing to cover the fixed shaft and the torsion spring.

Preferably, the knob is provided with a through opening, the fixed block is provided in the through opening, a first abutment block is provided on one side of the through opening of the knob, and a second abutment block is provided on one side of the fixed block corresponding to the first abutment block. When the knob is rotated to make the first abutment block abut against the second abutment block, the fixed block can be driven to cause the axis to rotate.

Preferably, the plug block does not protrude into the first plug slot when inserted into the second plug slot.

Preferably, the limit block includes a sheet body, the abutment block and the positioning hook are respectively protruding from the two ends of the sheet body, a sleeve block is provided on one side of the sheet body, and the compression spring is sleeved on the sleeve block and abuts against the inner side of the socket.

Preferably, the sleeve block is protruding from one side of the sheet body, and includes a connecting section and an extending section, the connecting section is connected to the sheet body, the extending section is connected to the connecting section and is separated from the sheet body by a predetermined distance, and the compression spring is sleeved on the extending section.

Preferably, a slot is provided at the bottom inner side of the socket, and the positioning hook can be hooked into the slot to fix the limit block in the socket.

Preferably, the inner wall of the head casing is provided with a plurality of transition curved surfaces and each of the limiting grooves, and each of the limiting grooves extends between adjacent transition curved surfaces.

Preferably, the extension direction of each limiting groove is parallel to the axial direction of the winding tube.

The present invention:

10: Roller blind pre-tightening limit spring stop structure

12: Torsion spring assembly

14: Knob assembly

16: Drive assembly

18: Making the head shell

22: Spring connector

24: Spring bracket

26: Fixed axis

28: Torsion spring

30: Ring

32: Composite pipe department

34: Plug-in pipe

36: Inner tube

38: External pipe

40: Positioning block

42: Tube body

44: Embedded card block

46: Positioning block

48: Knob

50:Fixed block

52: Ring

54: Passage

56: First opening

58: Second opening

60:Stage

62: First plug-in slot

64: First contact block

66: Teeth

68: Second socket

69: Card block

70: Second contact block

72: Axis

74: Limit block

76: Compression spring

78: Shaft

80: Plug block

82:Connection part

84:Shaft hole

86: Recessed

88:Protruding ring

90: Small path section

92: Main diameter section

94: Locking parts

96: Snap-on part

98: Socket

100: Environmental Protection Department

102: Management Department

104: Card slot

106: Film body

108: Butt block

110: Positioning hook

112: Socket block

114: Connection section

116: Extension section

118: Cylinder

120: socket

122: Baffle

124: Transition surface

126: Limiting groove

Usage:

1: Reel

2: Fixed bracket

The first figure is a three-dimensional combination diagram of a preferred embodiment of the present invention.

The second figure is a three-dimensional exploded view of a preferred embodiment of the present invention.

The third figure is a three-dimensional diagram of the knob in a preferred embodiment of the present invention.

The fourth figure is a three-dimensional diagram of the fixed block in a preferred embodiment of the present invention.

The fifth figure is a three-dimensional exploded view of the drive assembly in a preferred embodiment of the present invention.

Figure 6 is a three-dimensional diagram of the head casing in a preferred embodiment of the present invention.

Figure 7 is a partial cross-sectional view of a preferred embodiment of the present invention, showing the combined structure of the knob assembly, the drive assembly, the head housing and the spring joint, the fixed shaft, the torsion spring, and the fixed frame.

Figure 8 is a partial cross-sectional view of a preferred embodiment of the present invention, showing the combined structure of the spring bracket, fixed shaft, and torsion spring.

Below, a preferred embodiment of the present invention is given, and further detailed description is given with the help of drawings as follows:

Please refer to the first to eighth figures, a preferred embodiment of the present invention is a roller curtain pre-tensioning limit spring head structure 10, which is arranged on a roller curtain, and the roller curtain includes a roller tube 1, a curtain cloth (not shown), two fixing frames 2 and the roller curtain pre-tensioning limit spring head structure 10 and other mechanisms. The roller tube 1 is rotatably arranged between the two fixing frames 2, and the curtain cloth is connected to the roller tube 1 and can be rolled up or released. The roller curtain pre-tensioning limit spring head structure 10 is arranged on the inner side of the roller tube 1 and connected to the fixing frame 2, so as to provide The roller curtain is provided with a pre-tightening force to stop the roller tube 1 from rotating when the action of pushing up or pulling down the curtain stops. The two fixing frames 2 are used to fix the roller curtain to an indoor installation position, such as a window frame or a ceiling. The roller curtain is a known type with a curtain that can be pushed up or pulled down. The detailed structure of the roller tube 1, the curtain and the fixing frame 2 of the roller curtain is not described here. The roller curtain pre-tightening limit spring head structure 10 includes a torsion spring assembly 12, a knob assembly 14, a drive assembly 16 and a head housing 18.

As shown in the second, seventh and eighth figures, the torsion spring assembly 12 is located inside the winding tube 1 and is composed of a spring joint 22, a spring bracket 24, a fixed shaft 26 and a torsion spring 28. The spring joint 22 has a ring 30 and a composite tube portion 32 connected to both sides of the ring 30 and a plug tube 34. The composite tube portion 32 has an inner tube 36 and an outer tube 38 extending outside the inner tube 36. There is a predetermined gap between the inner tube 36 and the outer tube 38. Two positioning blocks 40 spaced 180 degrees apart are protruded from the outer side of the outer tube 38. The inner side of the plug tube 34 is connected to the inner tube 36. The spring bracket 24 has a tube body 42 and a plurality of locking blocks 44 protruding from one end of the tube body 42. Two positioning blocks 46 protruding from the outer side of the tube body 42 are 180 degrees apart. Each of the locking blocks 44 is provided for the winding tube 1 to be placed on the outer side and relatively locked and fixed. One end of the fixed shaft 26 is inserted between the inner tube 36 and the outer tube 38 of the spring joint 22, and the other end passes through the inner side of the tube body 42 and protrudes from the spring bracket 24. The torsion spring 28 is inserted and sleeved on the outer side of the fixed shaft 26, and the two ends are respectively sleeved on the outer sides of the outer tube 38 and the tube body 42 to abut the ring 30 and the embedded block 44. In addition, the two ends of the torsion spring 28 are respectively inserted and fixed by the positioning blocks 40 and 46 on the outer sides of the outer tube 38 and the tube body 42. The winding tube 1 is inserted and sleeved on the outer side of the torsion spring 28.

As shown in the second, third and fourth figures, the knob assembly 14 is composed of a knob 48 and a fixing block 50. The knob 48 has a ring-shaped ring body 52, the central part of which forms a hollow opening 54, the opening 54 has a first opening 56 and a second opening 58 connected, and the connection between the first and second openings 56 and 58 forms a step 60. One side of the ring body 52 is provided with a first insertion groove 62 connected to the first opening 56, and the other side is provided with a first abutment block 64 protruding from one side of the second opening 58. In addition, the outer side of the ring body 52 is provided with a tooth portion 66 to facilitate the rotation of the knob 48. The fixing block 50 is generally disc-shaped and can be inserted into the inner side of the first opening 56 and rotated in the first opening 56. A second plug-in slot 68 is provided on one side, and a clamping block 69 and a second abutting block 70 are provided on the other side. The second plug-in slot 68 can be connected to the first plug-in slot 62 (when the knob 48 and the fixing block 50 rotate relative to each other until the second plug-in slot 68 corresponds to the first plug-in slot 62). The second abutting block 70 can abut against the first abutting block 64 when the knob 48 rotates relative to the fixing block 50, so that the fixing block 50 can be driven by the knob 48 to rotate. In addition, the clamping block 69 is a rectangular body.

As shown in the second and fifth to seventh figures, the drive assembly 16 is composed of a shaft 72, a stopper 74 and a compression spring 76. The shaft 72 has a shaft portion 78, a plug block 80 and a connecting portion 82 connected between the shaft portion 78 and the plug block 80. The shaft portion 78 is generally cylindrical, with a shaft hole 84 passing through the shaft center, and an annular recess 86 and a convex ring 88 at both ends. The shaft hole 84 has a small diameter section 90 and a large diameter section 90 connected. The large diameter section 92 is located at one end of the corresponding recess 86. The recess 86 is for the plug-in tube 34 of the spring connector 22 to be plugged in. A locking member 94 is used to lock the large diameter section 92 into the small diameter section 90 and the inner side of the plug-in tube 34, thereby connecting the shaft 78 and the spring connector 22. The locking member 94 is a screw. The plug-in block 80 is generally in the shape of a T-shaped sheet, which is inserted into the second plug-in slot 68 and does not protrude into the first plug-in slot 62 (the knob 48 can rotate relative to the fixed block 50 without being blocked by the plug-in block 80), so that the axis 72 is connected to the fixed block 50 of the knob assembly 14. The connecting portion 82 is generally in the shape of a round rod, and has a clamping portion 96 at one end corresponding to the shaft portion 78, and a socket 98 is concavely provided on the top side. The clamping portion 96 has a ring 100 and a tube 102 protruding from the inner side of the ring 100. The ring 100 is plugged into the inner side of the convex ring 88, and the tube 102 is inserted into the large diameter section 92, so that the connecting portion 82 can be connected to the shaft portion 78. The cross section of the socket 98 is generally L-shaped, and a clamping groove 104 is provided at the inner bottom end. The limit block 74 is movably inserted into the insertion hole 98, and has a sheet 106, an abutment block 108, a positioning hook 110 and a set of abutment blocks 112. The abutment block 108 is protruded from the top of the sheet 106, and the positioning hook 110 is elastically offset and protrudes from the bottom of the sheet 106. The limit block 74 is made of a plastic material, but not limited to a plastic material. Therefore, the positioning hook 110 protruding from the bottom of the sheet 106 has appropriate elasticity to be offset, and can be hooked in the slot 104 when the limit block 74 moves to the bottom of the insertion hole 98, so that the limit block 74 is fixed in the insertion hole 98. , the sleeve block 112 is protruding from one side of the sheet 106, and has a connecting section 114 and an extension section 116. The connecting section 114 is connected to the sheet 106, and the extension section 116 extends downward from the connecting section 114 and is separated from the sheet 106 by a predetermined distance. The compression spring 76 is sleeved on the extension section 116 (the distance between the extension section 116 and the sheet 106 is slightly larger than the diameter of the compression spring 76) and abuts against the bottom side of the insertion hole 98, so that when the positioning hook 110 is not hooked into the card slot 104, the limit block 74 is subjected to the tension of the compression spring 76 and moves upward to abut against the head casing 18.

The head housing 18 is rotatably sleeved on the outer side of the shaft 72 and has a hollow cylindrical body 118. The end of the cylinder 118 corresponding to the knob assembly 14 is provided with a ring-shaped socket 120 for inserting and fixing one end of the reel 1 so that the head housing 18 can rotate with the rotation of the reel 1. The inner ring of the cylinder 118 is provided with a baffle 122. The baffle 122 extends into the corresponding ends of the shaft portion 78 and the connecting portion 82 and the outer side of the convex ring 88. , so that the head housing 18 can only rotate but cannot move relative to the shaft portion 78 or the connecting portion 82. The inner wall of the cylinder 118 outside the baffle 122 is provided with two transition curved surfaces 124 and two limiting grooves 126. The two limiting grooves 126 extend between adjacent transition curved surfaces 124, that is, the two limiting grooves 126 are 180 degrees apart, and the extension direction of each limiting groove 126 is parallel to the axial direction of the winding tube 1. Based on this, when the positioning hook 110 is not hooked in the card slot 104, the limiting block 74 is subjected to the tension of the compression spring 76 and abuts against the transition curved surface 124 or the limiting groove 126 with the abutting block 108.

Thus, the roller blind pre-tensioning limit spring head structure 10 of the present invention can be used to pre-tighten the roller blind before it leaves the factory (i.e., twist the torsion spring 28 to maintain a certain pre-tightening force). Its operation method, characteristics and functions are as follows: When the roller blind pre-tightening limit spring head structure 10 is pre-tightened, the knob 48 is turned. When the knob 48 is rotated until the first abutment block 64 and the second abutment block 70 are in abutment with each other, the fixed block 50 can be subjected to The shaft 72 can be driven to rotate by the fixed block 50 through the connection relationship of the plug block 80, so that the limit block 74 elastically abutting against the inner wall of the head housing 18 can slide along the transition curved surface 124 or slide into the limit groove 126 as the shaft 72 rotates. When the shaft 72 rotates, the spring connector 22 connected to it can also rotate, thereby twisting the torsion spring 28 and generating a pre-tightening force.

Next, when the torsion spring 28 is pre-tightened by rotating the knob 48 for a preset number of turns (the number of turns is determined by factors such as the weight of the curtain fabric and other components of the roller blind and the elastic force of the torsion spring 28, which is a known technique in the art, and a person skilled in the art can change and adjust the position according to the above factors), the limit block 74 can be located at a position where it slides into the limit groove 126 (during the process of rotating the knob 48). When the limit block 74 slides into the limit groove 126, it can still slide out of the limit groove 126 by the rotational force of the shaft 72. When the knob 48 is not rotated and the shaft 72 is not rotated, the wall of the limit groove 126 can prevent the limit block 74 from sliding out, thereby preventing the shaft 72 from reversing and maintaining the pre-tightening force. The head housing 18 is restricted by the top support of the limit block 74 and cannot rotate in the opposite direction.

Based on this, after the pre-tightening action of the roller blind pre-tightening limit spring head structure 10 is completed, the fixing block 50 can be connected to the fixing frame 2. The method is to first insert the clamping block 69 of the fixing block 50 into a rectangular receiving opening 126 provided on the fixing frame 2 so that the fixing block 50 and the fixing frame 2 will not rotate relative to each other, and then use a number of connecting parts (such as screws, etc., not shown in the figure) to pass through the fixing frame 2 to connect the fixing block 50, so that the fixing block 50 can be fixed to the fixing frame 2 and the roller blind is completed.

When consumers install the roller blind, they only need to fix the fixing frame 2 at the indoor installation position. After the installation is completed, the head housing 18 is still limited by the limit block 74 and cannot rotate, so the roller tube 1 connected to the head housing 18 cannot rotate and the roller blind cannot work normally. At this time, they only need to use a tool such as a screwdriver to press the limit block 74 into the socket 98. When the positioning hook 110 hooks the card slot 104, the limit block 74 can be fixed in the socket 98 and no longer protrudes, thereby releasing the limit block 74 on the head housing 18, and the roller blind can work normally.

As can be seen from the above, the roller blind pre-tightening limit spring head structure provided by the present invention, through the cooperation of the torsion spring assembly, the knob assembly, the driving assembly, the head housing, the winding tube, and the fixing frame, only needs to rotate the knob for a preset number of turns to drive the axial rotation spring joint to torsion the torsion spring, so that the torsion spring generates a pre-tightening force, and when the pre-tightening action is completed, the limit block is clamped in the limit groove on the inner side of the head housing, so that the head can be tightened. The head outer shell and the limit block produce a relative limit effect to prevent the axis from reversing, so as to maintain the pre-tightening force of the torsion spring. The pre-tightening action is very convenient and reliable. After installing the roller curtain, the consumer only needs to press the limit block into the socket, and the roller curtain can operate normally. When the consumer installs the roller curtain, there is no need to perform the pre-tightening action. The installation action is very convenient and has practical value. Therefore, this invention does meet the requirements of the invention patent, and an application is filed in accordance with the law.

The above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Anyone with common knowledge in the relevant technical field may make some modifications, changes and embellishments without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of the attached patent application.

10: Roller blind pre-tightening limit spring stop structure

12: Torsion spring assembly

18: Making the head shell

24: Spring bracket

26: Fixed axis

28: Torsion spring

1: Reel

2: Fixed bracket

Claims (10)

A roller curtain pre-tightening limit spring stopper structure is arranged between a fixing frame and a roller tube at one end of a roller curtain, and is used to provide a pre-tightening elastic force to stop the roller tube from rotating when the roller curtain stops pushing up or pulling down, and includes: A torsion spring assembly, comprising a spring joint, a spring bracket, a fixed shaft and a torsion spring, wherein the two ends of the fixed shaft are fixedly connected to the spring joint and the spring bracket, the torsion spring is sleeved on the outer side of the fixed shaft and between the spring joint and the spring bracket, and the winding tube is sleeved on the outer side of the torsion spring and connected to the spring bracket; A knob assembly, comprising a knob in a ring shape, on which a first plug-in slot is provided, and a fixing block, which is complementary arranged on the inner side of the knob, on which a second plug-in slot is provided, and the second plug-in slot is connected to the first plug-in slot; A driving assembly includes a shaft, a limit block and a compression spring. The shaft includes a shaft, a plug block and a connecting portion connected between the shaft and the plug block. The shaft is connected to the spring connector. The plug block is inserted into the second plug slot so that the shaft is connected to the knob assembly. When the knob assembly is rotated, the spring connector can be driven by the shaft. The head rotates, thereby rotating the torsion spring, causing the torsion spring to generate a pre-tightening elastic force. The connecting portion is recessed with a socket, and the limit block is inserted into the socket, including an abutment block and a positioning hook. The positioning hook can be elastically offset and protrudes from one end of the limit block, and can be hooked on the inner side of the socket. The compression spring is between the inner side of the socket and the limit block; and A head casing is cylindrical, sleeved on the outer side of the shaft and connected to the winding tube, and its inner wall is provided with a plurality of limiting grooves. When the positioning hook is not hooked on the inner side of the insertion hole, the limiting block is subjected to the tension of the compression spring and the abutting block abuts against the inner wall of the head casing or the limiting groove. When the abutting block abuts against the limiting groove, the relative rotation of the driving assembly and the head casing can be limited. As described in claim 1, the roller blind pre-tightening limit spring head structure, wherein the fixing block is fixed to a fixing frame of the roller blind by a plurality of connecting parts after the torsion spring generates a pre-tightening force, and the fixing frame is used to fix the roller blind at an indoor installation position. As described in claim 1, the roller blind pre-tensioning limit spring head structure, wherein the two ends of the roller tube are sleeved on the outer side of the spring bracket and the head housing to cover the fixed shaft and the torsion spring. As described in claim 1, the roller blind pre-tension limit spring head structure, wherein the knob is provided with a through hole, the fixed block is provided in the through hole, a first abutment block is provided on one side of the through hole of the knob, and a second abutment block is provided on one side of the fixed block corresponding to the first abutment block, when the knob is rotated to make the first abutment block abut against the second abutment block, the fixed block can be driven to cause the axis to rotate. The roller blind pre-tightening limit spring head structure as described in claim 1 or 4, wherein the plug block does not protrude into the first plug slot when inserted into the second plug slot. As described in claim 1, the roller blind pre-tension limit spring head structure, wherein the limit block includes a sheet, the abutment block and the positioning hook are respectively protruding at two ends of the sheet, a sleeve block is provided on one side of the sheet, and the compression spring is sleeved on the sleeve block and abuts against the inner side of the socket. As described in claim 6, the roller blind pre-tensioning limit spring head structure, wherein the sleeve block is protruding from one side of the sheet body, comprising a connecting section and an extension section, the connecting section is connected to the sheet body, the extension section is connected to the connecting section and is separated from the sheet body by a predetermined distance, and the compression spring is sleeved on the extension section. As described in claim 6, the roller blind pre-tightening limit spring head structure, wherein a slot is provided at the bottom inner side of the socket, and the positioning hook can be hooked into the slot to fix the limit block in the socket. As described in claim 1, the roller blind pre-tensioning limit spring head structure, wherein the inner wall of the head housing is provided with a plurality of transition curved surfaces and each limit groove, and each limit groove extends between adjacent transition curved surfaces. As described in claim 9, the roller blind pre-tensioning limit spring stopper structure, wherein the extension direction of each limit groove is parallel to the axial direction of the roller tube.