CN209471512U - A secondary box type object storage device - Google Patents

Abstract

A two-level box-type item storage and delivery device, which stores and delivers box-type items through a second-level box-type item storage and delivery system; the boxed goods to be sold are stored in two levels in the automatic vending device, and passed through The conveying mechanism carries out conveying and replenishment; the two-level storage is to store the boxed goods for sale in the storage system formed by the combination of the chain storage conveying system and the door and window storage system, wherein the chain storage conveying system is the main storage conveying System, the door and window storage system is a supplementary storage system, which is supplemented by the door and window storage system to the chain storage and conveying system. The utility model stores the boxed goods in the boxed goods automatic vending device in the low temperature environment through the secondary storage system, and then realizes the automatic vending of the boxed goods through the automatic vending system, which can realize a large stock of boxed goods. The automatic sales of items is not only convenient, but also can reduce service personnel and save labor costs.

Description

A secondary box type object storage device

technical field

The utility model relates to a storage method and device for automatic vending, in particular to a storage device for boxed goods (such as fast food, set meals, boxed pastries, etc., which are packed in boxes) using a secondary box-type item storage device. According to the method and device for storing and transporting, the storage capacity of the boxed items for automatic vending can be enlarged, which is convenient for customers to consume; it belongs to the technical field of vending.

Background technique:

With the changes of the times, people's consumption concept in the market is also changing. In the past, the concept of completely relying on shopping in stores in the market and eating in restaurants has been completely broken, especially in the recent hot development of "Meituan Waimai". It has caused a fundamental change in the diet of many people. Many young people rely entirely on "takeaway" for their lives; and in recent years, unmanned vending projects have become more and more popular among entrepreneurs. For example, now Well-known domestic Internet companies such as Ali, Xiaomi, JD.com, and Suning are all setting up unmanned supermarkets one after another, which greatly shows that unmanned vending has a good market prospect.

This may be the embryonic form of the new retail market. I believe that in the next five to ten years, vending machines will gradually replace labor and become the mainstream offline. Now we often see beverage self-service vending machines in schools, squares, parks, scenic spots and other places, but the current machines are generally launched by beverage manufacturers or machine factories, the main purpose is to promote brand image.

Statistics show that as of the end of 2016, the stock of self-service vending machines in my country was about 190,000 units. Since 2011, my country's self-service vending machine industry has developed rapidly. As of 2016, the market size of the industry has increased by more than 14 times compared with 2011. On the whole, the volume of vending machines in my country has grown rapidly, but compared with my country's huge population base, the overall penetration rate of self-service vending machines in my country is still very low. According to a survey by the Japan Self-Service Vending Machine Industry Association in 2016, there are about 5.8 million self-service vending machines in Japan (corresponding to a population of 120 million people, about 24 people own one), and 6.91 million units in the United States (corresponding to a population of 310 million people, about 44 person owns one). Compared with Japan and the United States, the penetration rate of self-service vending machines in my country still has great room for development. There is a huge gap with the U.S. and Japanese markets, and the inventory in 2022 will exceed 1.4 million units. Therefore, my country's self-service vending industry still has a lot of room for development.

But existing automatic vending machines generally just carry out simple goods sales, especially for box-packed articles (such as packaged meals, fast food, cakes, etc. with packing boxes), although there are some corresponding technical solutions, but the current market The automatic food vending machines that are locked and implemented all have too small storage capacity, which is not conducive to the automatic sale of packaged items, and the goods are inconvenient to ship and pick up. It is necessary to manually go to the automatic food vending machine to take them out, so there is still room for improvement. to improve.

No patent literature reports on the same technology as the utility model are found through patent retrieval, and the patents that have a certain relationship with the utility model mainly include the following:

1. The patent application number is CN201510177056, and the name is "cloud-controlled automatic meal vending machine". system, food transport system, heating system, constant temperature refrigeration system, monitoring system, sterilization and deodorization device and cloud control system, the chassis is provided with front door, side door and rear door hinged with the body of the chassis, control system, food transport system, heating system, constant temperature refrigeration system, monitoring system, and sterilization and deodorization devices are respectively set inside the cabinet, and the ordering system is set on the front door. The constant temperature refrigeration system, monitoring system, sterilization and deodorization device and cloud control system are all connected to the control system. The food delivery system includes vertical motion motors, horizontal motion motors, food delivery platforms, food delivery platform movement motors, and QR code scanners. And the electric push rod of the meal delivery platform, the vertical movement motor is installed on the vertical support rod, the horizontal movement motor is installed on the horizontal support rod, the movement motor of the meal delivery platform, the QR code scanner and the electric push rod of the meal delivery platform are respectively installed On the food delivery platform, the food delivery platform is connected to the horizontal support rod, and the horizontal support rod is connected to the vertical support rod. The horizontal movement motor drives the food delivery platform to move horizontally, and the vertical movement motor drives the food delivery platform to make vertical movement. The heating system It includes a microwave heating device and an electric push rod for the microwave heating device. The constant temperature refrigeration system includes a refrigeration device and a condensation device. The monitoring system includes a video device and an audio device. The sterilization and deodorization device includes an ozone generator.

2. The patent application number is CN201610197808, and the name is "Automatic Meal Vending Machine". The applicant is: Zhejiang Jiafeng Electromechanical Co., Ltd.'s invention patent application. This patent discloses an automatic meal vending machine, including the body. A machine door is provided, the door is hinged with the machine body, a cash register system and a human-computer interaction system are provided on the door, and a coin return button and a coin return port are also provided on the machine door. Both the coin button and the coin return port are fixedly connected with the machine door, and the inside of the machine body is equipped with a storage system, a heating system, a delivery system, a remote monitoring system and a control system, and the storage system, the heating system, the delivery system, Both the remote monitoring system and the cash register system are electrically connected to the control system, the storage system is provided with a refrigerator, the refrigerator is fixedly connected to the body, the heating system includes a microwave heater, and the microwave heater It is fixedly connected with the body, and the inside of the microwave heater is provided with a magnetron, and the magnetron is fixedly connected with the microwave heater, and the magnetron is connected with a waveguide and a coupling antenna. Both the wave tube and the coupling antenna are fixedly connected with the microwave heater, and the cargo delivery system includes a vertical lifter, a horizontal mover and a delivery platform, and the delivery platform is fixedly connected with the horizontal mover, and the horizontal mover The device is fixedly connected with the vertical lifter, and the cargo delivery system also includes a pick-up port, the pick-up port is set on the machine door, and the pick-up port is provided with a shooting sensor, and the shooting sensor It is fixedly connected with the pick-up port, the cargo delivery platform includes a microwave oven door, a guide plate is provided on the microwave oven door, the guide plate is fixedly connected with the microwave oven door, and an electric control block is provided between the guide plates. The electric control block is movably connected with the microwave oven door.

3. The patent application number is CN201410717760, and the name is "a method and automatic food vending machine for automatically selling food". The applicant is an invention patent application of Shenzhen Crazy Left Hand Information Technology Co., Ltd., which discloses an automatic food selling machine A method for food products and an automatic meal vending machine. The method includes: receiving an instruction to purchase a meal product, the purchase order including additional information about the meal product; judging whether the additional information about the meal product includes heating information, and if so, controlling the robot to transfer the The meal is grabbed from the freezing/refrigerating device to the heating device for heating; after the heating is completed, the control robot grabs the meal from the heating device to the heat preservation device, and the heat preservation device is connected to the delivery device; judging Whether the food in the heat preservation device is shipped within the preset time, if not, the robot will grab the unshipped food to the recovery room. The quality of the meal is guaranteed, and it is convenient and quick, and the robot is used to grab the meal, which can make more reasonable use of space than the existing belt conveyor, reduces the volume of the automatic meal vending machine, and reduces the cost.

Through careful analysis of the above-mentioned patents, although these patents all relate to automatic vending methods and devices, some improved technical solutions have also been proposed, but through careful analysis, these vending methods proposed are still limited to ordering meals or simple Vending device, for some sales problems of boxed catering, such as how to prevent the package from being crushed during storage and sales, there is no effective solution. Therefore, there are still some limitations, which are not conducive to general promotion and use. Still to be further studied.

Utility model content

The purpose of this utility model is to provide a secondary box-type article storage device for the existing automatic sales of boxed goods, which have a small amount of goods stored and are inconvenient for delivery and pickup. The second-level box-type article storage device can Effectively increase the quantity of stored boxed items, and realize unattended automatic sales of boxed items such as boxed lunches and set meals to meet various needs of the market.

In order to achieve this purpose, the utility model provides a two-level box-type article storage and delivery device. The second-level box-type article storage and delivery device includes a second-level box-type article storage and delivery system. Classification is stored in the secondary box type item storage and delivery system.

Further, the secondary box-type article storage and conveying system includes a chain storage and conveying system and a door and window storage system, and the chain storage and conveying system and the door and window storage system are combined to form a second-level box-type article storage and conveying system.

Further, the secondary box-type article storage and conveying system is all installed on the inner surface of the vending device, wherein the chain storage and conveying system is installed inside the box of the vending device, and the door and window storage system is installed on the inside of the vending device. The inside of the door panel.

Further, the chain storage and conveying system stores the boxed goods to be sold in layers in the automatic vending device through the interval of the chain, and the door and window storage system stores the boxed goods to be sold with the corresponding number of layers of the chain storage and conveying system. The bracket type is stored behind the door of the automatic vending device as a whole, and after the chain storage and conveying system is sold, the boxed goods for sale on the door and window storage system bracket are pushed into the chain storage and conveying system as a whole, and the chain storage and conveying system Carry out automatic replenishment of goods.

Further, the chain storage and conveying system is provided with a chain, the chain is fixed by two upper and lower flanges, respectively, and a drive motor is installed to implement synchronous driving; the lunch box is placed on the chain, and the chain is provided with a prevention box The limit block for the movement of the lunch box when the vehicle is running; when the motor runs at a certain angle, the chain runs, and at the same time the lowest lunch box falls on the bottom of the meal vending machine due to the change of the chain angle, and the bottom is equipped to prevent the lunch box from falling off. limit plate.

Further, the door and window storage system is provided with a bracket on the inner side of the door panel to store the lunch box. The bracket is provided with a limit block to prevent the lunch box from moving when the vehicle is running. rod; when all the lunch boxes on the chain are output, the linear slide pushes the push rod to push all the lunch boxes stored on the door panel bracket to the chain, and stores and transports through the chain.

Further, the chain storage and transportation system is a chain structure, each chain storage and transportation system is provided with two chains, the chain is fixed by two flanges, and the two flanges are installed on the bracket, respectively The upper flange and the lower flange form a chain connection structure; the shape of each flange matches the structure of the chain, and the outer periphery of the flange has a groove that catches the hinge pin of the chain, so that the hinge of the chain When the hinge pin moves to the flange plate, the hinge pin is stuck in the groove of the flange plate to form a clamping connection and is driven by the flange plate to rotate; at least one of the upper and lower flange plates of the two chains is equipped with a drive motor , the two chains are driven synchronously to ensure that the two chains simultaneously drive the box of the boxed item to run synchronously.

Further, the chain is a one-shaped hinge pin connection chain, and an "L" structure lunch box pallet is connected through the hinge pin in the middle of the one-shaped hinge pin connection chain, and the "L" structure lunch box The top of the pallet is connected to the chain through a hinge pin to form a pallet that can swing around the hinge pin. The boxes of boxed items are placed on the lunch box pallet and move from top to bottom along with the chain, and are placed in the dining box. A limit block is arranged on the box supporting plate to prevent the box of the boxed item from moving when the box of the boxed item is in operation.

Further, the door and window storage system is arranged on the back of the door panel of the automatic vending device; on the back of the door panel of the automatic vending device, a door panel bracket is provided on the inner surface of the chain storage and transportation system for storing boxed items, and the door panel The bracket is provided with a door and window storage system limit block that prevents the movement of the boxed items during operation.

Further, a linear slide and a push rod are installed on the inner surface of the door panel, and the push rod is connected with the linear slide through fasteners, and is driven by a stepping motor to move back and forth; when all the lunch boxes on the chain are output Finally, the linear slide pushes the push rod, and the push rod pushes all the lunch boxes stored on the door panel bracket to the chain of the chain storage and transportation system for storage and transportation through the chain.

The utility model has the advantages of:

The utility model effectively utilizes the internal space of the automatic vending device, adopts a secondary storage system for storing boxed goods, and adopts an overall push mode for replenishment, which can effectively replenish goods between the secondary box storage systems, and has the advantages of The following advantages:

1. The secondary box-type storage system adopting the chain storage and conveying system and the door and window storage system can effectively double the storage quantity in the original space and meet the needs of automatic sales of box-type packaging;

2. The double-wheel synchronous drive of the flange with grooves can effectively ensure the stability of the conveying process and avoid errors;

3. At the bottom of the chain storage and conveying system, the chain angle is changed to make the lunch box fall. Since it falls on the bottom of the meal vending machine, it can effectively avoid damage to the lunch box. At the same time, there is a limit plate at the bottom to prevent the lunch box from falling off. Accurate positioning of the fall;

4. The door and window storage system can automatically carry out the replenishment of the chain storage and conveying system through the overall movement of the linear slide table and the push rod, so as to improve the working efficiency.

Description of drawings

Fig. 1 is a schematic diagram of the overall structure of an embodiment of the utility model;

Fig. 2 is a three-dimensional schematic diagram of a chain storage and conveying system according to an embodiment of the present invention;

Fig. 3 is a schematic structural diagram of a chain storage and conveying system according to an embodiment of the present invention

Fig. 4 is a schematic diagram of a three-dimensional structure of a door and window storage system according to an embodiment of the present invention;

Fig. 5 is a schematic side sectional view of the structure of the door and window storage system according to an embodiment of the present invention;

Fig. 6 is an enlarged schematic view of the bottom structure of the chain storage and conveying system according to an embodiment of the present invention;

Fig. 7 is an enlarged schematic diagram of the pushing structure of the door and window storage system according to an embodiment of the present invention.

Detailed ways

The utility model will be further elaborated below in conjunction with the accompanying drawings and specific embodiments.

Embodiment one

The utility model relates to a secondary box-type article storage and delivery device, the second-level box-type article storage and delivery device includes a second-level box-type article storage and delivery system, and all goods for sale are stored in the second-level box-type according to order and classification. Item storage and conveying system.

The two-level box-type article storage and delivery system includes a chain storage delivery system and a door and window storage system; wherein, the chain storage delivery system stores the boxed goods to be sold in layers in the vending device through the interval of the chain, and the door and window The storage system stores the boxed goods to be sold behind the door of the automatic vending device in a bracketed manner according to the number of layers of the chain storage and conveying system. The sold boxed goods are pushed into the chain storage and conveying system, and the goods are automatically replenished to the chain storage and conveying system.

The chain storage and conveying system is provided with a chain, and the chain is fixed by two upper and lower flanges, respectively, and a driving motor is installed to implement synchronous driving; The limit block for the movement of the lunch box; when the motor runs at a certain angle, the chain runs, and at the same time, the lowermost lunch box falls to the bottom of the meal vending machine due to the change of the chain angle, and the bottom is equipped with a limit plate to prevent the lunch box from falling off .

The door and window storage system is provided with a bracket on the inner side of the door panel to store the lunch box. The bracket is provided with a limit block to prevent the lunch box from moving when the vehicle is running, and a linear slide and a push rod are installed at the same time; After all the lunch boxes on the chain are output, the linear slide pushes the push rod to push all the lunch boxes stored on the door panel bracket to the chain, and stores and transports them through the chain.

Below in conjunction with accompanying drawing, the utility model is further described;

As can be seen from accompanying drawings 1-7, the secondary box-type article storage and delivery system of the present utility model is an automatic storage and delivery system for a boxed set meal, and the second-level box-type article storage and delivery system includes a chain storage delivery system 1 And the door and window storage system 2, the chain storage delivery system 1 and the door and window storage system 2 are combined to form a secondary box-type article storage and delivery system 3; the second-level box-type article storage and delivery system 3 is all installed on the inner surface of the vending device 4, Wherein, the chain storage conveying system 1 is installed inside the box body of the automatic vending device 4, and the door and window storage system 2 is installed on the inner surface of the door panel 16 of the automatic vending device 4; the specific structure is described as follows:

1. Motor-driven chain storage and transportation system

The chain storage and transport system includes the following parts:

A. The chain storage and transportation system 1 is a chain structure, each chain storage and transportation system 1 is provided with two chains 5, the chains 5 are fixed by two flanges 6, and the two flanges 6 are installed on the bracket 22 , which are the upper flange 7 and the lower flange 8 respectively, forming a chain connection structure; the shape of each flange 6 matches the structure of the chain 5, and the outer periphery of the flange 6 has a hinge pin that blocks the chain The groove 9 makes the hinge pin 10 at the hinge of the chain 5 move to the flange, and the hinge pin 10 is stuck in the groove 9 of the flange to form a clamping connection, and is driven by the flange 6 to rotate; At least one of the upper and lower flanges of the two chains 5 is equipped with a drive motor 11, and the two chains 5 are driven synchronously to ensure that the two chains 5 simultaneously drive the lunch box 12 to run synchronously;

B. The chain 5 described above is a one-shaped hinge pin connection chain, and an "L" structure lunch box pallet 14 is connected through the hinge pin 13 in the middle of the one-shaped hinge pin connection chain, and the "L" structure The top of the lunch box pallet 14 is connected on the chain 5 by the hinge pin 13, forming a pallet that can swing around the hinge pin, the lunch box 12 is placed on the lunch box pallet 14, and follows the chain 5 from top to bottom Movement, and on the lunch box supporting plate 14, be provided with the limit block 15 that prevents the lunch box 12 from moving when the lunch box 12 is in operation;

C. When the driving motors 11 of the two chains 5 synchronously drive the chains 5 to run, the chains 5 move from top to bottom. There will be an angle change, and the lowermost lunch box will break away from the lunch box supporting plate 14 due to the angle change of the chain 5 and fall on the bottom of the meal vending machine.

2. Meal vending machine door panel bracket meal box storage and delivery system

The door and window storage system 2 is arranged on the back side of the door panel 16 of the automatic vending device 4; on the back side of the door panel 16 of the automatic vending device 4, a door panel bracket 17 is provided towards the inner surface of the chain storage and transportation system 1 to store meals. Box 12, the door panel bracket 17 is provided with the door and window storage system limit block 18 that prevents the lunch box 12 from moving during operation; meanwhile, a linear slide 19 and a push rod 20 are installed on the inner surface of the door panel 16, and the push rod 20 is fastened The parts are connected with the linear slide table 19, and are driven by the stepping motor 21 to move forward and backward; The stored meal boxes 12 are all pushed onto the chain of the chain storage and transportation system 1, and stored and transported by the chain.

The above-listed embodiments are only a clear and complete description of the technical solution of the utility model in conjunction with the accompanying drawings; obviously, the described embodiments are only part of the embodiments of the utility model, rather than all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

The utility model has the advantages of:

The utility model effectively utilizes the internal space of the automatic vending device, adopts a secondary storage system for storing boxed goods, and adopts an overall push mode for replenishment, which can effectively replenish goods between the secondary box storage systems, and has the advantages of The following advantages:

1. The secondary box-type storage system adopting the chain storage and conveying system and the door and window storage system can effectively double the storage quantity in the original space and meet the needs of automatic sales of box-type packaging;

2. The double-wheel synchronous drive of the flange with grooves can effectively ensure the stability of the conveying process and avoid errors;

3. At the bottom of the chain storage and conveying system, the chain angle is changed to make the lunch box fall. Since it falls on the bottom of the meal vending machine, it can effectively avoid damage to the lunch box. At the same time, there is a limit plate at the bottom to prevent the lunch box from falling off. Accurate positioning of the fall;

4. The door and window storage system can automatically carry out the replenishment of the chain storage and conveying system through the overall movement of the linear slide table and the push rod, so as to improve the operation efficiency.

At present, most of the meal vending machines in the civilian market are heated and stored, and the taste of the meal is poor. At the same time, the storage capacity of the meal box is small, and there will be a large market for cold meal heating products. After canceling the microwave heating function, the product can be transformed into a cold food vending machine, which can sell various foods such as ice cream and fruit. The variety of storage of this product can be expanded into various types of automatic storage and retrieval equipment.

Claims (10)

1. a kind of second level boxlike object storing and conveying device, it is characterised in that: second level boxlike object storing and conveying device packet Second level boxlike object storing and transportation system are included, all cargos for sale are in sequence with classified storage in second level boxlike object storing And in transportation system.

2. second level boxlike object storing as described in claim 1 and conveying device, it is characterised in that: the second level boxlike object Product storage and transportation system include chain storing/conveying system and door and window stocking system, are stored up by chain storing/conveying system and door and window Deposit system combines to form second level boxlike object storing and transportation system.

3. second level boxlike object storing as claimed in claim 2 and conveying device, it is characterised in that: the second level boxlike object Product storage and transportation system are all mounted on automatic vending device inner face, wherein chain storing/conveying system is mounted on automatic selling Goods device box inner face, door and window stocking system are mounted on the door-plate inner face of automatic vending device.

4. second level boxlike object storing as claimed in claim 3 and conveying device, it is characterised in that: the chain storage is defeated System is sent to carry out stratified storage in automatic vending device to box-packed cargo for sale by the interval of chain, door and window stocking system Box-packed cargo for sale is integrally stored in automatic vending device to correspond to chain storing/conveying system number of plies progress stent-type Behind the door, whole by the box-packed cargo for sale on door and window stocking system bracket and after the sale of chain storing/conveying system It is pushed into chain storing/conveying system, cargo is carried out to chain storing/conveying system and is automatically replenished.

5. second level boxlike object storing as claimed in claim 4 and conveying device, it is characterised in that: the chain storage is defeated System is sent to be equipped with chain, chain is fixed by upper and lower two ring flanges, respectively and is equipped with driving motor, is carried out synchronous driving；Meal Box is placed on chain, and chain, which is equipped with, prevents cutlery box mobile limited block of cutlery box in vehicle operation；When motor operating is certain Angle, chain operation, while the cutlery box of lowest part falls in meals-selling machine bottom due to chain angle change, while bottom is set Having prevents cutlery box from falling inclined limit plate.

6. second level boxlike object storing as claimed in claim 4 and conveying device, it is characterised in that: the door and window stores system System is to be equipped with bracket in door-plate inner face side, and for storing cutlery box, bracket, which is equipped with, prevents cutlery box movement in vehicle operation Limited block, while straight line slide unit and push rod being installed；After the cutlery box on chain all output, straight line slide unit pushes push rod The cutlery box stored on door-plate bracket is all pushed on chain, is stored and is transported by chain.

7. second level boxlike object storing as claimed in claim 4 and conveying device, it is characterised in that: the described chain storage and Transportation system is chain structure, and the storage of each chain and transportation system are equipped with two chains, and chain is consolidated by two ring flanges Fixed, two ring flanges are rack-mount, respectively upper flange plate and lower flange, form chain connection structure；Each method The shape of blue disk and the structure of chain match, and the outer periphery of ring flange has the groove for blocking chain hinge pin, so that the hinge of chain When moving on ring flange, hinge pin is stuck in the groove of ring flange the hinge pin at the place of connecing, and forms clamping, and by ring flange band turn It is dynamic；On two chains lower flange at least one driving motor is installed, two chains carry out synchronous driving, to guarantee two Chain drives the box of boxlike article to run simultaneously simultaneously.

8. second level boxlike object storing as claimed in claim 7 and conveying device, it is characterised in that: the chain is a word Type hinge pin connects chain, is connected with a L-shaped structure cutlery box support again by hinge pin in the centre of "-" type hinge pin connection chain The top of plate, L-shaped structure cutlery box supporting plate is connected on chain by hinge pin, forms the supporting plate that can be swung around hinge pin, The box of boxlike article is placed on cutlery box supporting plate, and as chain moves from top to bottom, and on cutlery box supporting plate be equipped with prevent The mobile limited block of the box of the box of boxlike article boxlike article at runtime.

9. second level boxlike object storing as claimed in claim 4 and conveying device, it is characterised in that: the door and window stores system It unites on the back side for the door-plate that automatic vending device is set；At the door-plate back side of automatic vending device, stores and transport towards chain The inner face of defeated system is equipped with door-plate bracket and is used to store boxlike article, and door-plate bracket, which is equipped with, prevents boxlike article from moving at runtime Dynamic door and window stocking system limited block.

10. second level boxlike object storing as claimed in claim 9 and conveying device, it is characterised in that: the door-plate inner face On straight line slide unit and push rod are installed, push rod is connected together by fastener and straight line slide unit, and by stepper motor drive front and back Movement；After the cutlery box on chain all output, straight line slide unit pushes push rod, the cutlery box that push rod will store on door-plate bracket It is all pushed on the chain of chain storage and transportation system, is stored and transported by chain.