Telescopic frame locking structure

Abstract

A telescopic frame locking structure, characterized in that: the locking structure comprises two locking assemblies, which are symmetrically arranged on the inner sides of fixed rods of a left vertical rod and a right vertical rod. The locking assemblies comprise fixing blocks, locking pins, and springs; the fixing blocks are fixed to the inner sides of the fixed rods of the left vertical rod and the right vertical rod; a through-hole is transversely formed at each fixing block; the locking pins pass through the through-holes; the springs act on the locking pins; the elastic force of the springs forces the outer ends of the locking pins to extend into holes at the fixed rods, thereby allowing insertion fit with positioning holes at telescopic rods; the inner ends of the locking pins first bend radially to form radially bent sections and then extend axially; the radially bent sections abut against the end surfaces of the fixing blocks; the inner ends of the locking pins of the two locking assemblies are connected by means of a sleeve; and the inner ends of the locking pins can axially slide relative to the sleeve.

Description

A telescopic frame locking structure Technical Field

[0001] This invention relates to trolleys or ladder racks, and more particularly to a telescopic rack locking structure for trolleys or ladder racks. Background Technology

[0002] Trolleys are widely used in logistics, express delivery, and warehousing as handling tools, and are popular due to their simplicity, convenience, low cost, and high efficiency. Modern trolleys also need to have telescopic and folding functions to reduce their size and facilitate storage, thus meeting consumers' demands for convenience.

[0003] A representative example of a trolley, as described in invention patent number CN201825071U, consists of a pull rod, a bracket, and a base plate. One side of the bracket has wheels, and the other side has the base plate. The pull rod is positioned upwards at the top of the bracket. The pull rod comprises a left upright, a right upright, a crossbar connecting the middle of the left and right uprights, and a handle connecting the tops of the left and right uprights. The left and right uprights can be telescopic rods to achieve a telescopic function. Since telescopic rods are used, a telescopic locking structure is required. Currently available locking structures are either overly complex and costly, or lack sufficient load-bearing capacity and reliable locking. Summary of the Invention

[0004] The purpose of this invention is to provide a telescopic frame locking structure that is simple in structure, low in cost, and has good load-bearing capacity and high reliability after locking.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is: a telescopic frame locking structure, wherein the telescopic frame has a left upright and a right upright, both of which are composed of a fixed rod and a telescopic rod nested together, and the telescopic rod is provided with multiple positioning holes;

[0006] The locking structure includes two locking components, symmetrically arranged on the inner sides of the fixing rods of the left and right uprights. Each locking component includes a fixing block, a locking pin, and a spring. The fixing block is fixed to the inner side of the fixing rods of the left and right uprights. A through hole is provided on the fixing block along the transverse direction. The locking pin passes through the through hole. The spring acts on the locking pin, and the spring force forces the outer end of the locking pin to pass through the hole on the fixing rod for engagement with the positioning hole on the telescopic rod. The inner end of the locking pin is first bent radially to form a radially bent section and then extends axially. The radially bent section abuts against the end face of the fixing block. The inner ends of the locking pins of the two locking components are connected by a sleeve, and the inner end of the locking pin can slide axially relative to the sleeve.

[0007] Specifically, the end face of the fixed block that abuts against the radially bent section is provided with an circumferentially curved surface, and a first position point and a second position point are provided on the curved surface. When the radially bent section of the locking pin abuts against the first position point, the outer end of the locking pin passes through the hole on the fixed rod due to the elastic force of the spring, so as to engage with the positioning hole on the telescopic rod to achieve a locking state. When the radially bent section of the locking pin abuts against the second position point, the locking pin overcomes the spring force and exits to achieve an unlocking state.

[0008] In the above scheme, the through hole of the fixing block is a stepped hole, and its large hole section is installed facing the fixing rod. The length of the large hole section is greater than that of the small hole section. The spring is set in the large hole section, and the spring is a compression spring. Its inner end abuts against the stepped surface of the stepped hole, while its outer end is positioned on the pin of the locking pin by a fastener.

[0009] Furthermore, the fixing block is fixed to the inner surface of the fixing rod by rivets.

[0010] In the above scheme, the working surface has a first position point and two second position points; the two second position points are located at the top and bottom, while the first position point is located in the middle, so that when the sleeve is moved, when the sleeve is at the highest position, the radially bent section of the locking pin is close to the upper second position point to achieve the unlocked state; when the sleeve is at the middle position, the radially bent section of the locking pin is close to the first position point to achieve the locked state; and when the sleeve is at the lowest position, the radially bent section of the locking pin is close to the lower second position point to achieve the unlocked state.

[0011] In the above scheme, when the radially bent section of the locking pin is close to the first position point, the outer end of the locking pin passes through the fixing rod and the telescopic rod due to the elastic force of the spring, so that its outer end is exposed on the outer side of the fixing rod to achieve the locking state.

[0012] The effects of this invention are:

[0013] 1. Since the present invention uses the radial bending section of the locking pin to abut against the end face of the fixing block to achieve the conversion between unlocking and locking, the locking components on both sides can be unlocked simultaneously by pushing the sleeve up or down, which is more ergonomic and makes the operation smoother by using arm strength.

[0014] 2. Similarly, since this invention uses the radial bending section of the locking pin to abut against the end face of the fixing block to achieve the switching between unlocking and locking, and the fixing block is similar to a cam, the locking reliability is high and the load-bearing capacity is good.

[0015] 3. Also, since the present invention uses the radial bending section of the locking pin to abut against the end face of the fixing block to achieve the conversion between unlocking and locking, the overall structure is relatively simple and the implementation cost is not high. Attached Figure Description

[0016] Figure 1 is a schematic diagram of the application of Embodiment 1 of the present invention to a trolley;

[0017] Figure 2 is a structural cross-sectional view of Embodiment 1 of the present invention;

[0018] Figure 3 is a three-dimensional schematic diagram of the fixing block structure in Embodiment 1 of the present invention;

[0019] Figure 4 is a schematic diagram of the partial disintegration and explosion of the present invention applied to a cart according to Embodiment 1 of the present invention.

[0020] In the above image:

[0021] 1. Telescopic frame; 2. Left upright; 3. Right upright; 4. Fixed pole; 5. Telescopic pole; 6. Bent pole;

[0022] 7. Locking components;

[0023] 71. Fixed block; 711. Through hole; 712. Actual surface; 7121. First position point; 7122. Second position point;

[0024] 72. Locking pin; 721. Radial bend section;

[0025] 73. Spring;

[0026] 74. Card firmware;

[0027] 75. Rivets;

[0028] 8. Sleeve. Detailed Implementation

[0029] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0030] Example 1: Referring to Figures 1-4, a telescopic frame locking structure is shown below:

[0031] The telescopic frame 1 is applied to a trolley, as shown in Figure 1. The telescopic frame 1 has a left upright 2 and a right upright 3, both of which are nested together by a fixed rod 4 and a telescopic rod 5. The telescopic rod 5 has multiple positioning holes. Specifically, the top ends of the left upright 2 and the right upright 3 are connected by a bent rod 6.

[0032] The locking structure includes two locking components 7, which are symmetrically arranged on the inside of the fixing rods 4 of the left upright 2 and the right upright 3, one on the left and one on the right.

[0033] The locking assembly 7 includes a fixing block 71, a locking pin 72, and a spring 73. The fixing block 71 is fixed to the inner side of the fixing rod 4 of the left upright 2 and the right upright 3. A through hole 711 is provided on the fixing block 71 laterally. The locking pin 72 passes through the through hole 711. The spring 73 acts on the locking pin 72, and the elastic force of the spring 73 forces the outer end of the locking pin 72 to pass through the hole on the fixing rod 4 for engagement with the positioning hole on the telescopic rod 5. The inner end of the locking pin 72 is first bent radially to form a radially bent section 721 and then extends axially. The radially bent section 721 abuts against the end face of the fixing block 71. The inner ends of the locking pins 72 of the two locking assemblies 7 are connected by a sleeve 8, and the inner end of the locking pin 72 can slide axially relative to the sleeve 8.

[0034] Specifically, the end face of the fixing block 71 that abuts against the radially bent section 721 is provided with a circumferentially curved surface 712. This curved surface 712 has a first position point 7121 and a second position point 7122. During use, by moving the sleeve 8 up and down, when the radially bent section 721 of the locking pin 72 abuts against the first position point 7121, the outer end of the locking pin 72, due to the elastic force of the spring 73, passes through the hole on the fixing rod 4, allowing it to engage with the positioning hole on the telescopic rod 5 to achieve a locked state. When the radially bent section 721 of the locking pin 72 abuts against the second position point 7122, the locking pin 72 overcomes the spring force and retracts to achieve an unlocked state.

[0035] The fixing block 71 has a stepped hole, with its larger section facing the fixing rod. The length of the larger section is greater than that of the smaller section. A spring 73, which is a compression spring, is installed inside the larger section. Its inner end rests against the stepped surface of the stepped hole, while its outer end is positioned on the pin of the locking pin 72 by a fastener 74. The fixing block 71 is fixed to the inner surface of the fixing rod 4 by a rivet 75.

[0036] Referring to Figure 3, the operating surface 712 has a first position point 7121 and two second position points 7122. The two second position points 7122 are located at the top and bottom, while the first position point 7121 is located in the middle. This design allows the sleeve 8 to be moved as follows: when the sleeve 8 is in its highest position, the radially bent section 721 of the locking pin 72 abuts against the upper second position point 7122 to achieve an unlocked state; when the sleeve 8 is in its middle position, the radially bent section 721 of the locking pin 72 abuts against the first position point 7121 to achieve a locked state; and when the sleeve 8 is in its lowest position, the radially bent section 721 of the locking pin 72 abuts against the lower second position point 7122 to achieve an unlocked state. This design makes operation extremely convenient, allowing the user to unlock the sleeve by moving it up or down according to their preference.

[0037] Specifically, when the radially bent section 721 of the locking pin 72 is close to the first position point 7121, the outer end of the locking pin 72 passes through the fixing rod 4 and the telescopic rod 5 due to the elastic force of the spring 73, so that its outer end is exposed on the outer side of the fixing rod 4 to achieve the locking state. This design has the best load-bearing capacity.

[0038] In this embodiment, the locking components 7 on both sides can be unlocked simultaneously by moving the sleeve 8 up or down, which is more ergonomic and allows for smoother operation by using arm strength. Furthermore, the fixing block 71 is similar to a cam, which has high locking reliability, good load-bearing capacity, and a relatively simple overall structure with low implementation cost.

[0039] Example 2: A telescopic frame locking structure:

[0040] The locking structure of the telescopic frame in this embodiment is the same as that in Embodiment 1. The difference is that it is applied to the telescopic ladder to lock and unlock the telescopic uprights of the ladder.

[0041] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A telescopic frame locking structure, wherein the telescopic frame has a left upright and a right upright, both the left and right uprights being constructed by nesting a fixed rod and a telescopic rod, and the telescopic rod is provided with multiple positioning holes; characterized in that: The locking structure includes two locking components, symmetrically arranged on the inner sides of the fixing rods of the left and right uprights. Each locking component includes a fixing block, a locking pin, and a spring. The fixing block is fixed to the inner side of the fixing rods of the left and right uprights. A through hole is provided on the fixing block along the transverse direction. The locking pin passes through the through hole. The spring acts on the locking pin, and the spring force forces the outer end of the locking pin to pass through the hole on the fixing rod for engagement with the positioning hole on the telescopic rod. The inner end of the locking pin is first bent radially to form a radially bent section and then extends axially. The radially bent section abuts against the end face of the fixing block. The inner ends of the locking pins of the two locking components are connected by a sleeve, and the inner end of the locking pin can slide axially relative to the sleeve. Specifically, the end face of the fixed block that abuts against the radially bent section is provided with an circumferentially curved surface, and a first position point and a second position point are provided on the curved surface. When the radially bent section of the locking pin abuts against the first position point, the outer end of the locking pin passes through the hole on the fixed rod due to the elastic force of the spring, so as to engage with the positioning hole on the telescopic rod to achieve a locking state. When the radially bent section of the locking pin abuts against the second position point, the locking pin overcomes the spring force and exits to achieve an unlocking state.

2. The telescopic frame locking structure according to claim 1, characterized in that: The through hole of the fixing block is a stepped hole, and its larger hole section is installed facing the fixing rod. The length of the larger hole section is greater than that of the smaller hole section. The spring is installed in the larger hole section. The spring is a compression spring. Its inner end abuts against the stepped surface of the stepped hole, while its outer end is positioned on the pin of the locking pin by a fastener.

3. The telescopic frame locking structure according to claim 2, characterized in that: The fixing block is fixed to the inner surface of the fixing rod by rivets.

4. The telescopic frame locking structure according to claim 1, characterized in that: The working surface has a first position point and two second position points; the two second position points are located at the top and bottom, while the first position point is located in the middle, so that when the sleeve is moved, when the sleeve is in the highest position, the radially bent section of the locking pin is close to the upper second position point to achieve the unlocked state; when the sleeve is in the middle position, the radially bent section of the locking pin is close to the first position point to achieve the locked state; and when the sleeve is in the lowest position, the radially bent section of the locking pin is close to the lower second position point to achieve the unlocked state.

5. The telescopic frame locking structure according to claim 1, characterized in that: When the radially bent section of the locking pin is close to the first position point, the outer end of the locking pin passes through the fixing rod and the telescopic rod due to the elastic force of the spring, so that its outer end protrudes from the outer side of the fixing rod to achieve the locking state.

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